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Liver fibrosis is characterized by chronic inflammatory responses and progressive fibrous scar formation. Macrophages play a central role in the pathogenesis of hepatic fibrosis by reconstructing the immune microenvironment. Picroside II (PIC II), extracted from Picrorhizae Rhizoma, has demonstrated therapeutic potential for various liver damage. However, the mechanisms by which macrophage polarization initiates immune cascades and contributes to the development of liver fibrosis, and whether this process can be influenced by PIC II, remain unclear. In the current study, RNA sequencing and multiple molecular approaches were utilized to explore the underlying mechanisms of PIC II against liver fibrosis in multidrug-resistance protein 2 knockout (Mdr2−/−) mice. Our findings indicate that PIC II activates M1-polarized macrophages to recruit natural killer cells (NK cells), potentially via the CXCL16-CXCR6 axis. Additionally, PIC II promotes the apoptosis of activated hepatic stellate cells (aHSCs) and enhances the cytotoxic effects of NK cells, while also reducing the formation of neutrophil extracellular traps (NETs). Notably, the anti-hepatic fibrosis effects associated with PIC II were largely reversed by macrophage depletion in Mdr2−/− mice. Collectively, our research suggests that PIC II is a potential candidate for halting the progression of liver fibrosis. [ABSTRACT FROM AUTHOR]

Background Picroside II (PII), an iridoid glycoside extracted from the rhizomes and stems of the genus Picroside, exhibits pronounced hepatoprotective properties. Pre-administration of PII protects against acute liver injury caused by D-galactosamine (D-Gal), carbon tetrachloride (CCl4), and acetaminophen (APAP). This study aimed to elucidate the ramifications of PII administration subsequent to the initiation of acute hepatic injury. Methods Exploring the role of PII treatment in APAP-treated cell and rat models and in D-Gal and CCl4-treated rat models. Results In rats, APAP treatment increased serum aspartate transaminase, alanine transaminase, and alkaline phosphatase levels and decreased glutathione activity and the fluidity of the liver mitochondrial membrane. In L-02 cells, APAP exposure resulted in a decrement in membrane potential, an augmentation in the liberation of reactive oxygen species, and an acceleration of apoptotic processes. Moreover, PII pre-administration protected against D-Gal-induced acute hepatic injury and CCl4-induced chronic hepatic injury in rodent models, whereas PII administration post-injury aggravated CCl4-induced chronic hepatic injury. Conclusions Our results suggest that the effects of PII depend on the hepatic physiological or pathological state at the time of intervention. While PII possesses the potential to avert drug-induced acute hepatic injury through the mitigation of oxidative stress, its administration post-injury may exacerbate the hepatic damage, underscoring the critical importance of timing in therapeutic interventions. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effect of Picroside Ⅱ on inflammatory response and NF-κB/MAPK signaling pathway in rats with allergic asthma. Methods: The rat model of allergic asthma was established by ovalbumin sensitization and aerosol inhalation.The rats with successful modeling were randomly divided into model group, Picroside Ⅱ group and activator group (C16-PAF group), and the healthy rats without modeling were selected as control group, with 8 rats in each group. After the modeling, the rats in the Picroside Ⅱ group (C16-PAF group) were given Picroside Ⅱ at an intragastric dose of 80 mg/kg daily, and the rats in the C16-PAF group were given a daily intragastric dose of 80 mg/kg Picroside Ⅱ and 50 μL of C16-PAF solution (MAPK activator) at a concentration of 4 μmol/L, and the drug was administered for 14 days for each group. The rats in the model group were given the same amount of normal saline by intragastric administration, while the rats in the control group were given the same amount of normal saline by intraperitoneal injection, atomization inhalation and intragastric administration at the same period of modeling and administration, respectively. The rat lung function index of FVC, PEF, FEV0.3 and FEV0.3/FVC were recorded by whole body plethysmography. The pathological changes of rat lung were detected by hematoxylin-eosin (HE) staining. The counts of leukocytes, lymphocytes, eosinophils and neutrophils in the bronchoalveolar lavage fluid (BALF) of rats were analyzed by Reye’s staining. The levels of OVA-Ig E and ET-1 in serum and the levels of inflammatory factors IL-4, IL-5, IL-13 and IFN-γ in BALF were detected by ELISA. The expression levels of p-p38MAPK and p-NF-κBp65 in rat lung tissue were analyzed by immunohistochemical staining. The expression level of protein in NF-κB/MAPK signaling pathway were detected by Western blot. Results: In the control group, the basic structure and morphology of rat lung tissue were normal, and no inflammatory cell infiltration and tissue lesion were observed. In the model group, there was obvious inflammatory cell infiltration in rat lung tissue,and the wall of bronchial cavity was thickened, the lumen was shrunk, and the wall of alveolar cavity was thickened and severely damaged. The infiltration of lung inflammatory cells and the damage of alveolar and bronchial structures were significantly improved in the Picroside Ⅱ group. The injury of lung tissue in the C16-PAF group was similar to that in the model group, but the severity was slightly reduced. Compared with control group, the values of FVC, FEV0.3, FEV0.3/FVC and PEF in model group were decreased (P＜0.05), and the counts of lymphocytes, eosinophils, neutrophils, white blood cells, IL-4, IL-5 and IL-13 in BALF were increased (P＜0.05) . The levels of IFN-γ in BALF were decreased (P＜0.05), Ig E and ET-1 levels in serum were increased (P＜0.05), and the expression levels of p-NF-κBp65 and p-p38MAPK protein in rat lung tissue were increased (P＜0.05) . Compared with model group, the values of FVC, FEV0.3, FEV0.3/FVC and PEF in Picroside Ⅱ group were increased (P＜0.05), and the counts of lymphocytes, eosinophils, neutrophils, white blood cells, IL-4, IL-5 and IL-13 in BALF group were decreased (P＜0.05) . The level of IFN-γ in BALF was increased (P＜0.05), Ig E and ET-1 levels in serum were decreased (P＜0.05), and the expression levels of p-NF-κBp65 and p-p38MAPK in rat lung tissue were decreased (P＜0.05) . Compared with Picroside Ⅱ group, the values of FVC, FEV0.3, FEV0.3/FVC and PEF in C16-PAF group were decreased (P＜0.05), and the counts of lymphocytes, eosinophils, neutrophils, white blood cell, IL-4, IL-5 and IL-13 in BALF were increased (P＜0.05) . The level of IFN-γ in BALF was decreased (P＜0.05), Ig E and ET-1 levels in serum were increased (P＜0.05), and the expression levels of p-NF-κBp65 and p-p38MAPK in rat lung tissue were increased (P＜0.05) . Compared with the model group, there was no significant difference in all indexes in the C16-PAF group (P＞0.05) . Conclusion: Picroside Ⅱ may reduce the inflammatory process of asthmatic rats by inhibiting NF-κB/MAPK signaling pathway. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of picroside II on dexamethasone (DEX)-induced osteoblast apoptosis by regulating the receptor-interacting protein (RIP) 1/RIP3/mixed lineage kinase domain-like (MLKL) signal. Methods HFOB 1.19 cells were cultured in vitro and randomly grouped into control group, DEX group, DEX+picroside II group, DEX+RIP1 overexpression group, DEX+empty plasmid group, and DEX+picroside II+RIP1 overexpression group. After grouping treatment, cell viability rate, apoptosis rate, the relative level of reactive oxygen species (ROS), the releases of lactate dehydrogenase (LDH), interleukin (IL)-1β, tumor necrosis factor-α (TNF-α), IL-6, the relative expressions of BCL-2 and BAX, the expressions of RIP1/RIP3/MLKL signal proteins were detected in cells of each group. Results Compared to those in the control group, the cell viability and the relative expression of BCL-2 in DEX group decreased (P<0.05), the apoptosis rate, ROS relative level, LDH and IL-1β, TNF-α, IL-6 releases, and the relative expressions of BAX and RIP1, RIP3, MLKL proteins increased (P<0.05). Compared to those in DEX group, the cell viability and the relative expression of BCL-2 in DEX+picroside II group increased (P<0.05), the apoptosis rate, ROS relative level, LDH and IL-1β, TNF-α, IL-6 releases, and the relative expressions of BAX and RIP1, RIP3, MLKL proteins decreased (P<0.05). The cell viability and the relative expression of BCL-2 in the DEX+RIP1 overexpression group decreased (P<0.05), the apoptosis rate, ROS relative level, LDH and IL-1β, TNF-α, IL-6 releases, and the relative expressions of BAX and RIP1, RIP3, MLKL proteins increased (P<0.05). There was no obvious difference in cell indexes in DEX+empty plasmid group (P>0.05). Overexpression of RIP1 weakened the effect of picroside II on DEX induced hFOB 1.19 cells. Conclusion Picroside II reduces inflammation by down-regulating RIP1/RIP3/MLKL pathway, thus inhibiting the apoptosis of osteoblasts induced by DEX. [ABSTRACT FROM AUTHOR]

Nerve injury induced microglia activation, which released inflammatory mediators and developed neuropathic pain. Picroside Ⅱ (PⅡ) attenuated neuropathic pain by inhibiting the neuroinflammation of the spinal dorsal horn; however, how it engaged in the cross talk between microglia and neurons remained ambiguous. This study aimed to investigate PⅡ in the modulation of spinal synaptic transmission mechanisms on pain hypersensitivity in neuropathic rats. We investigated the analgesia of PⅡ in mechanical and thermal hyperalgesia using the spinal nerve ligation (SNL)-induced neuropathic pain model and formalin-induced tonic pain model, respectively. RNA sequencing and network pharmacology were employed to screen core targets and signaling pathways. Immunofluorescence staining and qPCR were performed to explore the expression level of microglia and inflammatory mediator mRNA. The whole-cell patch–clamp recordings were utilized to record miniature excitatory postsynaptic currents in excitatory synaptic transmission. Our results demonstrated that the analgesic of PⅡ was significant in both pain models, and the underlying mechanism may involve inflammatory signaling pathways. PⅡ reversed the SNL-induced overexpression of microglia and inflammatory factors. Moreover, PⅡ dose dependently inhibited excessive glutamate transmission. Thus, this study suggested that PⅡ attenuated neuropathic pain by inhibiting excitatory glutamate transmission of spinal synapses, induced by an inflammatory response on microglia. [ABSTRACT FROM AUTHOR]

Infectious bursal disease virus (IBDV) is a highly contagious virus with a dsRNA genome, predominantly infecting chickens and causing significant economic losses due to high mortality rates. The emergence of recombinant, novel variant, and highly virulent strains that evade current vaccines has led to frequent epidemics and outbreaks in the poultry industry. The lack of targeted antivirals for IBDV underscores the pressing requirement to develop potent therapeutic options. Within this framework, our research investigated the effectiveness of picroside II, a naturally derived iridoid glycoside, against viruses in DF-1 cells. Our findings demonstrate that picroside II significantly inhibits viral replication, with its efficacy increasing proportionally to the dosage administered. Through time-addition and antiviral duration analysis, we determined that picroside II therapeutically blocks IBDV replication, with its effects persisting for over 72 hours. Further investigation revealed that picroside II specifically inhibits the cellular replication stage of IBDV's lifecycle. Additionally, our findings indicate that picroside II impairs VP1 polymerase activity by binding to the active pocket, which significantly disrupts the interaction between VP1 and VP3. Mutations at three critical binding sites on VP1 not only impair virus replication but also hinder polymerase function and disrupt VP1-VP3 interactions. Collectively, these results demonstrate that picroside II, by inhibiting viral polymerase activity, represents a promising antiviral agent against IBDV. • Picroside II damages IBDV replication. • Picroside II binds to VP1 and inhibits its polymerase activity. • Mutations of active binding sites disrupt virus replication. [ABSTRACT FROM AUTHOR]

Background: Accumulation of free fatty acids (FFAs) in hepatocytes is a hallmark of liver dysfunction and non-alcoholic fatty liver disease (NAFLD). Excessive deposition of FFAs alters lipid metabolism pathways increasing the oxidative stress and mitochondrial dysfunction. Attenuating hepatic lipid accumulation, oxidative stress, and improving mitochondrial function could provide potential targets in preventing progression of non-alcoholic fatty liver (NAFL) to non-alcoholic steatohepatitis (NASH). Earlier studies with Picrorhiza kurroa extract have shown reduction in hepatic damage and fatty acid infiltration in several experimental models and also clinically in viral hepatitis. Thus, the effect of P. kurroa's phytoactive, picroside II, needed mechanistic investigation in appropriate in vitro liver cell model. Objective(s): To study the effect of picroside II on FFAs accumulation, oxidative stress and mitochondrial function with silibinin as a positive control in in vitro NAFLD model. Materials and methods: HepG2 cells were incubated with FFAs-1000μM in presence and absence of Picroside II-10 μM for 20 hours. Results: HepG2 cells incubated with FFAs-1000μM lead to increased lipid accumulation. Picroside II-10μM attenuated FFAs-induced lipid accumulation (33%), loss of mitochondrial membrane potential (ΔΨm), ATP depletion, and production of reactive oxygen species (ROS). A concomitant increase in cytochrome C at transcription and protein levels was observed. An increase in expression of MnSOD, catalase, and higher levels of tGSH and GSH:GSSG ratios underlie the ROS salvaging activity of picroside II. Conclusion: Picroside II significantly attenuated FFAs-induced-lipotoxicity. The reduction in ROS, increased antioxidant enzymes, and improvement in mitochondrial function underlie the mechanisms of action of picroside II. These findings suggest a need to develop an investigational drug profile of picroside II for NAFLD as a therapeutic strategy. This could be evaluated through the fast-track path of reverse pharmacology.

Ulcerative colitis (UC) is a common acute or chronic intestinal disease with an imbalance of inflammation. Picroside II (P-II) exerts a protective role in various inflammation-related diseases. However, the effect of P-II on UC is still unclear. To explore the effect of P-II on UC and its potential mechanism. Human monocytic leukemia cell line THP-1 was treated with phorbol ester (PMA) to differentiate into a macrophage. The differentiated THP-1 cells were hatched with LPS combined with ATP or Nigericin to activate the NLRP3 inflammasome in vitro. The UC model was constructed by injection of DSS into mice. The maximum nontoxic concentration of P-II on THP-1 cells was 60 μM. LPS combined with ATP or Nigericin stimulated the production of IL-1β, which was antagonized by P-II treatment. Meanwhile, P-II administration interfered with the aggregation of ASC and the assembly of NLRP3 inflammasomes. Also, P-II treatment reduced the LPS and ATP-induced elevation of the relative protein expression of NLRP3, pro-caspase-1, IL-1β and p-p65/p65, and the concentration of TNF-α and IL-6. Besides, the NF-κB specific inhibitor BAY-117082 notably repressed the LPS together with ATP-enhanced the relative protein expression of NLRP3, caspase-1 and IL-1β. Moreover, in vivo results showed that P-II relieved the DDS-induced UC, as evidenced by the improvement of mice weight, DAI and pathological scores. In addition, P-II treatment notably decreased DDS-promoted expression of NLRP3 inflammasomes and inflammatory factors in vivo. P-II alleviated DSS-induced UC by repressing the production of NLRP3 inflammasomes via the NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

Purpose: To develop and validate RP-HPLC method for simultaneous determination of four active ingredients: picroside I (PSI), picroside II (PSII), phyllanthin (PHY) and boeravinone-B (BVB) in a polyherbal hepatoprotective tablet formulation. Methods: The study was carried out using Waters X-Bridge, C18 (250 mm x 4.6 mm, 5 μm) column with mobile phase consisting of 5 mM ammonium acetate in 10 % methanol and acetonitrile, with gradient programme at dual wavelengths of 220 nm and 274 nm and flow speed of 1 mL.min-1. The procedure was validated with respect to specificity, linearity, precision, accuracy, system suitability, limit of detection (LOD) and of quantification (LOQ), and robustness in line with ICH specifications. Results: The method was linear within the concentration range of 25 to 200 %, and the values of correlation coefficients (R2) were > 0.999. Intra-day and inter-day RSDs of PAs and RTs were < 5.0 %, with recovery in the range of 100.0 - 106.0 %. Conclusion: The four active ingredients have with good resolution with regard to the method used. The method is rapid, simple, highly selective, sensitive and cost effective, which make it an efficient method for quality assurance. [ABSTRACT FROM AUTHOR]

Picroside II, an iridoid glycoside, has anti‐cancer, anti‐virus, anti‐apoptotic, nervous and myocardial protection effects and so on. However, the oral bioavailability of Picroside II is low, and the half‐life in vivo is short, so it is limited to use in clinic. Triazole is a highly stable heterocyclic ring, which can be interacted with various enzymes or receptors in the organism through non‐covalent interactions, and many of its good pharmacological activities in vitro and in vivo have been reported. Based on the advantages of triazole and Picroside II, a series of triazole‐modified Picroside II derivatives (5 a–5 i) were synthesized by using drug combination principles for the first time. The structures were confirmed by different spectroscopic techniques including 1H NMR, 13C NMR and HRMS, and the primary biological evaluation of anti‐breast cancer, anti‐colorectal cancer, the effect on SARS‐CoV‐2 3CLpro inhibitor, and CD47‐SIRPα protein were screened as well. Compound 5 e has anti‐breast cancer activity, and compounds 3 and 5 i have anti‐colorectal cancer activity. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To probe into the mechanism of picroside II inhibiting proliferation, invasion and metastasis of esophageal cancer Ecal09 cells through mitogen extracellular signal regulated kinase( MEK) I extracellular signal regulated kinase(ERK) pathway. METHODS: Human esophageal cancer cells Ecal09 were divided into normal culture group ( conventional culture), picroside II group ( 20 µmoVL of picroside II ), activator group ( 20 µmol/L of MEK/ERK signaling pathway activator) and picroside II +activator group ( 20 µmoVL of picroside II +20 µmoVL of MEK/ERK signaling pathway activator) . The proliferative activity of Ecal09 cells in each group was detected by tetrazolium salt method, the apoptosis and cycle of Ecal09 cells in each group were detected by flow cytometry, the cell invasive and metastasizing ability were detected by Transwell and scratch assay, the expression of apoptosis-related proteins, cycle-related proteins and MEK/ERK pathway-related proteins were detected by protein immunoblotting. RESULTS: Compared with the normal culture group, the inhibition rate of cell proliferation, apoptosis rate, Caspase3 and Bax protein expression, GO/GI phase and S phase ratio were increased in the picroside II group; the Bcl-2 protein, G2/ M phase ratio, invasion cell number, scratch healing rate, cell cycle-related proteins and MEK/ERK pathway-related proteins of picroside II group were decreased, with statistically significant differences ( P < 0. 05) . Compared with the normal culture group, the inhibition rate of cell proliferation, apoptosis rate, Caspase-3 and Bax protein expression, GO/GI phase and S phase ratio were decreased in the activator group; the Bcl-2 protein, G2/ M phase ratio, invasion cell number, scratch healing rate, cell cycle-related proteins and MEK/ERK pathway-related proteins of the activator group were significantly increased, with statistically significant differences ( P < 0. 05). Compared with the picroside II group, the inhibition rate of cell proliferation, apoptosis rate, Caspase-3 and Bax protein expression, G0/Gl phase and S phase ratio were decreased in the picroside II +activator group; the Bcl-2 protein, G2/M phase ratio, invasion cell number, scratch healing rate, cell cycle-related proteins and MEK/ERK pathway-related proteins of the picroside II + activator group were significantly increased, with statistically significant differences ( P < 0. 05). Compared with activator group, the inhibition rate of cell proliferation, apoptosis rate, Caspase-3 and Bax protein expression, GO/ G 1 phase and S phase ratio were increased in the picroside II +activator group; the Bcl-2 protein, G2/M phase ratio, invasion cell number, scratch healing rate, cell cycle-related proteins and MEK/ERK pathway-related proteins of the picroside II + activator group were significantly decreased, with statistically significant differences ( P < 0. 05). CONCLUSIONS: picroside II has a certain inhibitory effect on the proliferation, invasion and metastasis of esophageal cancer cells, probably through inhibiting the expression of MEK/ ERK pathway-related proteins. [ABSTRACT FROM AUTHOR]

Picrorhiza kurroa, the dried rhizome of Picrorhiza kurroa Royle ex Benth, is a famous Chinese herb that has been traditionally used in China. Picroside II (PII), a glycoside derivative, is the main bioactive constituent of Picrorhiza kurroa. In the past several decades, bioactive components from Picrorhiza kurroa have attracted the attention of researchers due to their promising therapeutic effects. A large number of studies have demonstrated the therapeutic potential of PII for the prevention and treatment of some diseases, such as organic ischemia/reperfusion (I/R) injury, liver damage, inflammation, cancer metastasis and angiogenesis. In the present paper, we aimed to provide an overview of the pharmacology of PII, focusing on its anti-oxidant, anti-inflammatory and anti-apoptotic activities. Meanwhile, the plant tissue distribution and pharmacokinetic properties were also described. Due to its beneficial pharmacological effects in I/R injury, PII may serve as a promising therapeutic agent for organic I/R injury prevention.

Cancer is one of the leading causes of death worldwide. The development of novel anti-cancer agents from natural products is a promising approach to reduce cancer mortality. In this study, we investigated the anti-metastatic and anti-angiogenic activities of picroside II (PII) in human breast cancer cells both in vitro and in vivo. Our results demonstrated that PII significantly inhibited the migration and invasion of MDA-MB-231 cancer cells. With the treatment of PII, the activity of matrix metalloproteinase 9 (MMP-9) in MDA-MB-231 cancer cells was significantly inhibited both in vitro and in vivo. Meanwhile, PII showed effective anti-metastatic activity in an experimental lung metastasis model. Interestingly, cluster of differentiation 31 (CD31), a marker of angiogenesis, was significantly downregulated in the PII-treated tumor samples, indicating the anti-angiogenic activity of PII. Furthermore, we demonstrated that PII significantly inhibited the migration, invasion, and tube formation of human umbilical vein endothelial cells (HUVECs). The inhibition of MMP-9 activity in PII-treated HUVECs was also demonstrated. Finally, the suppression of angiogenesis by PII in the chick embryo chorioallantoic membrane (CAM) was observed. In conclusion, our results demonstrated that PII effectively inhibited the metastasis and angiogenesis of cancer cells both in vitro and in vivo, and thus, might be a novel candidate for cancer therapy.

Background/Aims Hepatic steatosis is caused by an imbalance between free fatty acids (FFAs) uptake, utilization, storage, and disposal. Understanding the molecular mechanisms involved in FFAs accumulation and its modulation could drive the development of potential therapies for Nonalcoholic fatty liver disease. The aim of the current study was to explore the effects of picroside II, a phytoactive found in Picrorhiza kurroa, on fatty acid accumulation vis-à-vis silibinin, a known hepatoprotective phytoactive from Silybum marianum. Methods HepG2 cells were loaded with FFAs (oleic acid:palmitic acid/2:1) for 20 hours to mimic hepatic steatosis. The FFAs concentration achieving maximum fat accumulation and minimal cytotoxicity (500 μM) was standardized. HepG2 cells were exposed to the standardized FFAs concentration with and without picroside II pretreatment. Results Picroside II pretreatment inhibited FFAs-induced lipid accumulation by attenuating the expression of fatty acid transport protein 5, sterol regulatory element binding protein 1 and stearoyl CoA desaturase. Preatreatment with picroside II was also found to decrease the expression of forkhead box protein O1 and phosphoenolpyruvate carboxykinase. Conclusions These findings suggest that picroside II effectively attenuated fatty acid accumulation by decreasing FFAs uptake and lipogenesis. Picroside II also decreased the expression of gluconeogenic genes.

Picrorhiza scrophulariiflora Pennell, a well-known Chinese herb, has been traditionally utilized as an antioxidant and anti-inflammatory agent. One of its main bioactive components is Picroside II, a glycoside derivative. However, there is limited information on the effects of Picroside II on the activity of cytochrome P450 (CYP) enzymes nor on potential herb-drug interactions are rarely studied. The purpose of the study was to investigate the effects of Picroside II on the activity of cytochrome P450 enzymes in vitro and in vivo and its potential herb-drug interactions. Specific probe substrates were employed to assess the effect of Picroside II on the activity of P450 enzymes. The inhibitory effects of Picroside II on CYP enzymes were assayed both in human (i.e., 1A, 2C9, 2C19, 2D6, 2E1, and 3A) and rat (i.e., 1A, 2C6/11, 2D1, 2E1, and 3A) liver microsomes in vitro. The inductive effects were investigated in rats following oral gavage of 2.5 mg/kg and 10 mg/kg Picroside II. A specific Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry (UPLC-MS/MS) method was developed to determine the formation of specific metabolites. Enzyme inhibition results showed that Picroside II (0.5–200 μM) had no evident inhibitory effects on rat and human liver microsomes in vitro. Interestingly, the administration of multiple doses of 10 mg/kg Picroside II inhibited the activity of CYP2C6/11 by reducing the rate of formation of 4-hydroxydiclofenac and 4-hydroxymephenytoin, while Picroside II at 2.5 mg/kg increased the activity of CYP3A by promoting the formation of 1-hydroxymidazolam and 6-hydroxychlorzoxazone in rats. In addition, there were negligible effects on CYP1A, CYP2D1, and CYP2E1 in rats. The results indicated that Picroside II modulated the activities of CYP enzymes and was involved in CYP2C and CYP3A medicated herb-drug interactions. Therefore, careful monitoring is necessary when Picroside II is used in combination with related conventional drugs. [Display omitted] • Picroside II had no inhibition on CYP450s in human and rat microsomes in vitro. • Picroside II could inhibit CYP2C and induce CYP3A in rats in vivo. • Picroside II could cause herb-drug interactions via cytochrome P450. [ABSTRACT FROM AUTHOR]

Yiğit Kılıç,1 Abdullah Özer,1 Tolga Tatar,1 Mustafa Hakan Zor,1 Mehmet Kirişçi,2 Hakan Kartal,3 Ali Doğan Dursun,4 Deniz Billur,5 Mustafa Arslan,6 Ayşegül Küçük7 1Department of Cardiovascular Surgery, Gazi University Medical Faculty, Ankara, 2Department of Cardiovascular Surgery, Kahramanmaras Sutcu Imam Medical Faculty, Kahramanmaras, 3Department of Cardiovascular Surgery, Ardahan State Hospital, Ardahan, 4Department of Physiology, Ankara University Medical Faculty, 5Department of Histology and Embryology, Ankara University Medical Faculty, 6Department of Anaesthesiology and Reanimation, Gazi University Medical Faculty, Ankara, 7Department of Physiology, Dumlupinar University Medical Faculty, Kütahya, Turkey Introduction: Many structural and functional damages are observed in cells and tissues after reperfusion of previously viable ischemic tissues. Acute ischemia reperfusion (I/R) injury of lower extremities occurs especially when a temporary cross-clamp is applied to the abdominal aorta during aortic surgery. Research regarding the treatment of I/R injury has been increasing day-by-day. In this study, we aimed to investigate the effect of picroside II on skeletal muscle of rats experiencing simulated I/R.Materials and methods: Twenty-four male Wistar albino rats weighing between 210 and 300 g were used in this study. Rats were randomly divided into 4 groups of 6 rats each (control, I/R, control + picroside II, and I/R + picroside II). The infrarenal section of the abdominal aorta was occluded with an atraumatic microvascular clamp in I/R group. The clamp was removed after 120 minutes and reperfusion was provided for a further 120 minutes. Picroside II (10 mg kg–1) was administered intraperitoneally to the animals in control + picroside II and I/R + picroside II groups. At the end of the study, skeletal muscle tissue was obtained for the determination of total oxidant status (TOS) and total antioxidant status (TAS) levels. Apoptosis was evaluated by TUNEL experiment.Results: TOS levels were significantly higher in I/R group than that of control and I/R + picroside II groups (P=0.014, P=0.005, respectively). TAS levels were significantly higher in I/R group than that of control and I/R + picroside II groups (P=0.007 P=0.005, respectively). TUNEL assay revealed that picroside II reduced cell necrosis.Conclusion: The results of this study demonstrated that picroside II plays a critical role to prevent I/R injury. Even though our results were found to be satisfactory, it should be encouraging to those who want to conduct future research on this topic. Keywords: ischemia reperfusion, picroside II, hind limb skeletal muscle, TOS, TAS

Picroside II (P‐II), one of the main active components of scrophularia extract, which have anti‐oxidative, anti‐inflammatory effects, but its effect on hyperhomocysteinemia (HHcy) induced endothelial injury remains to be determined. Here, we test whether P‐II protects HHcy‐induced endothelial dysfunction against oxidative stress, inflammation and cell apoptosis. In vitro study using HUVECs, and in hyperhomocysteinemia mouse models, we found that HHcy decreased endothelial SIRT1 expression and increased LOX‐1 expression, subsequently causing reactive oxygen species generation, up‐regulation of NADPH oxidase activity and NF‐κB activation, thereby promoting pro‐inflammatory response and cell apoptosis. Blockade of Sirt1 with Ex527 or siRNASIRT1 increased LOX‐1 expression, whereas overexpression of SIRT1 decreased LOX‐1 expression markedly. P‐II treatment significantly increased SIRT1 expression and reduced LOX‐1 expression, and protected against endothelial cells from Hcy‐induced oxidative injury, inflammation and apoptosis. However, blockade of SIRT1 or overexpression of LOX‐1 attenuated the therapeutic effects of P‐II. In conclusion, our results suggest that P‐II prevents the Hcy induced endothelial damage probably through regulating the SIRT1/LOX‐1 signaling pathway. [ABSTRACT FROM AUTHOR]

Faruk Metin Çomu,1 Yiğit Kılıç,2 Abdullah Özer,2 Mehmet Kirişçi,3 Ali Doğan Dursun,4 Tolga Tatar,2 Mustafa Hakan Zor,2 Hakan Kartal,2 Ayşegül Küçük,5 Hakan Boyunağa,6 Mustafa Arslan71Department of Physiology, Kirikkale University Medical Faculty, Kirikkale, 2Department of Cardiovascular Surgery, Gazi University Medical Faculty, Ankara, 3Department of Cardiovascular Surgery, Necip Fazil State Hospital, Kahramanmaras, 4Department of Physiology, Ankara University Medical Faculty, Ankara, 5Department of Physiology, Dumlupinar University Medical Faculty, Kütahya, 6Department of Biochemistry, Kirikkale University Medical Faculty, Kirikkale, 7Department of Anaesthesiology and Reanimation, Gazi University Medical Faculty, Ankara, TurkeyBackground: Ischemia reperfusion injury (I/R) in hind limb is a frequent and important clinical phenomenon. Many structural and functional damages are observed in cells and tissues in these kinds of injuries. In this study, we aimed to evaluate the effect of picroside II on lipid peroxidation and erythrocyte deformability during I/R in rats.Methods: Rats were randomly divided into four groups – each containing six animals (sham, I/R, sham + picroside II, and I/R + picroside II). The infrarenal section of the abdominal aorta was occluded with an atraumatic microvascular clamp in I/R groups. The clamp was removed after 120 minutes and reperfusion was provided for a further 120 minutes. Picroside II (10 mg·kg-1) was administered intraperitoneally to the animals in the appropriate groups (sham + picroside II, I/R + picroside II groups). All rats were euthanized by intraperitoneal administration of ketamine (100 mg·kg-1) and taking blood from the abdominal aorta. Erythrocytes were extracted from heparinized complete blood samples. Buffer (PT) and then erythrocytes (PE) were passed through the filtration system and the changes in pressure were measured to investigate the role of serum malondialdehyde and nitric oxide (NO) in lipid peroxidation and erythrocyte deformability index.Results: Deformability index was significantly increased in the I/R group compared to groups sham, sham + picroside-II, and I/R + picroside-II (P

Reactive astrocyte-mediated neuroinflammatory responses in the spinal dorsal horn have been reported to play a pivotal role in pathological pain. Chronic constriction injury (CCI) enhances the activation of nuclear factor kappa B (NF-κB), which is involved in neuropathic pain (NP). Picroside II (PII), a major active component of Picrorhiza scrophulariiflora, has been investigated for its anti-oxidative, anti-inflammatory, and anti-apoptotic activities. Here, we explored the analgesic effects of PII on a model of CCI-induced NP and investigated the levels of the GFAP protein and the mRNA and protein levels of pro-inflammatory cytokines in the spinal cord, including interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). CCI significantly induced mechanical allodynia and thermal hyperalgesia. Intraperitoneal administration of PII remarkably reversed the CCI-induced mechanical allodynia and thermal hyperalgesia and reduced the mRNA and protein levels of IL-1β, IL-6, and TNF-α in the spinal cord. Additionally, according to the in vitro data, the PII treatment inhibited LPS-induced increases in the mRNA and protein levels of IL-1β, IL-6, and TNF-α and suppressed the NF-κB pathway by inhibiting the phosphorylation of NF-κB/p65 and the degradation of inhibitor of NF-κB (IκB) in astrocytes without toxicity to astrocytes. Overall, the analgesic effect of PII correlated with the inhibition of spinal reactive astrocyte-mediated neuroinflammation through the NF-κB pathway in rats with NP. [ABSTRACT FROM AUTHOR]

Background: Picrorhiza kurroa (PK) belongs to Scrophulariaceae family and is a representative endemic, medicinal herb, widely distributed throughout the higher altitudes of alpine Himalayas from west to east, between 3000 and 4500 m above mean sea level. Objective: The objective of the present study is to assess the production of picroside I and picroside II from tissue cultures of PK. Materials and Methods: Auxiliary shoot tips of PK were incubated in Murashige and Skoog medium supplemented with indole-3-butyric acid and kinetin phytohormones. The callus produced was collected at different time intervals and was processed for extraction of picroside I and picroside II followed by thin layer chromatography and high-performance liquid chromatography HPLC analysis. Results: The maximum growth index was found to be 5.109 ± 0.159 at 16-week-old callus culture. The estimation of picroside-I and picroside-II was carried out by (HPLC) analysis; quantity of secondary metabolite found to be 16.37 ± 0.0007 mg/g for PK-I and 6.34 ± 0.0012 mg/g for PK-II. Conclusion: This is the first attempt to produce the Picroside-I and II in large amount by the tissue culture technique. It can be observed that the method of callus culture can be used in production of secondary metabolites Picroside-I and II from PK [ABSTRACT FROM AUTHOR]

Chronic obstructive pulmonary disease (COPD) is a major inflammatory lung disease characterized by irreversible and progressive airflow obstruction. Although corticosteroids are often used to reduce inflammation, steroid therapies are insufficient in patients with refractory COPD. Both serum amyloid A (SAA) and IL-33 have been implicated in the pathology of steroid-resistant lung inflammation. Picroside II isolated from Pseudolysimachion rotundum var. subintegrum (Plantaginaceae) is a major bioactive component of YPL-001, which has completed phase-2a clinical trials in chronic obstructive pulmonary disease patients. In this study, we investigated whether picroside II is effective in treating steroid refractory lung inflammation via the inhibition of the SAA-IL-33 axis. Picroside II inhibited LPS-induced SAA1 expression in human monocytes, which are resistant to steroids. SAA induced the secretion of IL-33 without involving cell necrosis. Picroside II, but not dexamethasone effectively inhibited SAA-induced IL-33 expression and secretion. The inhibitory effect by picroside II was mediated by suppressing the mitogen-activated protein kinase (MAPK) p38, ERK1/2, and nuclear factor-κB pathways. Our results suggest that picroside II negatively modulates the SAA-IL-33 axis that has been implicated in steroid-resistant lung inflammation. These findings provide valuable information for the development of picroside II as an alternative therapeutic agent against steroid refractory lung inflammation in COPD.

Picroside II is the main active ingredient in the root department of Chinese medicine Picrorhiza scrophulariiflora which has been proved to have beneficial effects on health, such as ameliorating the cerebral ischemia and protecting the liver. However, its effects on acute lung injury remain unclear. The purpose of the study was to evaluate the effects of picroside II on acute lung injury in mice and the inflammation in A549 cells which are lipopolysaccharide (LPS) induced. We evaluated the levels of tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1β), and interleukin-6 (IL-6) in vivo and vitro by enzyme-linked immunosorbent assay (ELISA) and quantitative polymerase chain reaction (qRT-PCR). Results showed picroside II significantly decreased the concentrations of TNF-α, IL-1β, and IL-6 in cells and mice. In addition, Western blot and immunofluorescence analysis indicated that picroside II suppressed the activation of p65 NF-κB signaling pathway compared with LPS stimulation. In the acute lung injury model of mice, after picroside II treatment, the pathologic changes of lung tissues had been alleviated and lung wet/dry weight ratio was decreased. In summary, picroside II showed the promising effects of anti-inflammation in cells and animals. [ABSTRACT FROM AUTHOR]

Stroke is a common neurodegenerative disease in the wide world, and mitochondrial defects underlie the pathogenesis of ischemia, especially during reperfusion. Picroside II, the principal active component of Picrorhiza, is a traditional Chinese medicine. Our previous study demonstrated that the best therapeutic dose and time window were injection of picroside II at a dose of 10-20 mg/kg body weight following cerebral ischemia by 1.5-2.0 h. In this paper, the neuroprotective effect and the mechanism of picroside II were investigated, as well as its involvement in antioxidant and mitochondria cytochrome C (CytC) signal pathway following ischemia reperfusion (I/R) injury in rats. After 24 h of cerebral I/R, the neurobehavioral function was measured by modified neurological severity score test; the content of reactive oxygen species in brain tissue was measured by enzyme-linked immunosorbent assay; the cerebral infarction volume was detected by TTC staining; the morphology of brain tissue was observed by hematoxylin-eosin; the apoptotic cells were counted by terminal deoxynucleotidyl transferase dUTP nick end labeling assay; the ultrastructure of the cortical brain tissues was observation by transmission electron microscopy; the expressions of CytC and Caspase-3 were determined by immunohistochemical assay and Western blot. The results indicated that picroside II could scavenge ROS contents, decrease the cerebral infarction volume and apoptotic cells, protect the structure of mitochondria, down-regulate the expression of CytC and Caspase-3 in cerebral I/R rats. It can be concluded that picroside II exerts a neuroprotective effect by inhibiting the mitochondria CytC signal pathway following ischemia reperfusion injury in rats. [ABSTRACT FROM AUTHOR]

Objective: Diabates mellitus, is a chronic metabolic disorder accompanied by an increase in oxidative stress. Ischemia-reperfusion injury is a cascade of events initiated by tissue ischemia. The cellular damage produced by reperfusion leads to an active inflammatory response. This study was performed to investigate the effect of picroside II on myocardial ischemiareperfusion injury in rats with streptozotocin-induced diabetes. Methods: Animals were equally (n:6) divided for five groups as follows; Control (C), diabetes [D], diabetes+picroside II [DP], diabetes+I/R [DIR], and diabetes+I/R+ picroside II [DIRP]. In DIR group, a left anterior descending artery branch was occluded for 60 minutes, the reperfused for 120 minutes. In DIRP group, picroside II was administrated via 10 mg/kg intraperitoneal route 30 minutes before ligating the left anterior descending artery. At the end of the study, myocardial tissues were taken for total oxidant status and total antioxidant status level determinations. Results: Total oxidant status levels were significantly higher in DIR group, when compared with C, DP, and DIRP groups (p:0.001, p:0.019, and p:0.031, respectively). Total antioxidant status levels were significantly higher in DIR group, when compared with C, DP, and DIRP groups (p:0.006, p:0.024, and p:0.007, respectively). Conclusion: These results indicate that administration of picroside II may have protective effects against I/R injury. [ABSTRACT FROM AUTHOR]

The inflammatory response is important in the pathogenesis of myocardial ischemia/reperfusion (I/R) injury. Picroside II, the primary active constituent of Picrorhizae, has been reported to protect the myocardium from I/R-induced injury, however, the exact mechanism underlying these protective effects remains unclear. The aim of the present study was to investigate the mechanism underlying the protective effects of picroside II on I/R-induced myocardial injury. Adult male Sprague-Dawley rats underwent 1 h left coronary artery occlusion followed by 3 h reperfusion. Picroside II was administered (10 mg/kg) via the tail vein 30 min prior to left coronary artery occlusion. The results revealed that pretreatment of picroside II could significantly alleviate I/R-induced myocardial injury concomitantly with a decrease in inflammatory factor production. In addition, picroside II was also able to decrease high mobility group box 1 (HMGB1) expression, and release and downregulate the expression of the receptor for advanced glycation end products (RAGE), toll-like receptor (TLR)-2 and TLR-4. Furthermore, picroside II was able to inhibit nuclear factor-κB (NF-κB) activation. The results indicated that the protective effect of picroside II on I/R-induced myocardial injury was associated, at least partly, with inhibition of the inflammatory response by suppressing the HMGB1-RAGE/TLR-2/TLR-4-NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore the optimal therapeutic dose and time window of picroside II for treating cerebral ischemic injury in rats according to the orthogonal test. The middle cerebral artery occlusion (MCAO) models were established by intraluminally inserting a thread into middle cerebral artery (MCA) from left external carotid artery (ECA). The successful rat models were randomly divided into 16 groups according to the orthogonal layout of [L16(45)] and treated by injecting picroside II intraperitoneally with different doses at various times. The neurological behavioral function was evaluated by Bederson’s test and the cerebral infarction volume was measured by tetrazolium chloride (TTC) staining. The expressions of neuron specific enolase (NSE) and neuroglial mark-protein S-100 were determined by immunohistochemisty assay. The results indicated that the optimal compositions of the therapeutic dose and time window of picroside II in treating cerebral ischemic injury were ischemia 1.5 h with 20 mg/kg body weight according to Bederson’s test, 1.0 h with 20 mg/kg body weight according to cerebral infarction volume, 1.5 h with 20 mg/kg body weight according to the expressions of NSE and S-100 respectively. Based on the principle of the minimization of medication dose and maximization of therapeutic time window, the optimal composition of the therapeutic dose and time window of picroside II in treating cerebral ischemic injury should be achieved by injecting picroside II intraperitoneally with 20 mg/kg body weight at ischemia 1.5 h.

The aim of this study was to explore the effect of picroside II on neuronal apoptosis and the expression of caspase-3 and poly ADP-ribose polymerase (PARP) following middle cerebral artery occlusion/reperfusion in male Wistar rats. Picroside II (10 mg/kg) was administered intravenously into the tail vein of the animals. The neurological function deficits were evaluated with the Bederson’s test and the cerebral infarction volume was visualized with tetrazolium chloride (TTC) staining. The apoptotic cells were counted by in situ terminal deoxynucleotidyl transferase-mediated biotinylated deoxyuridine triphosphate nick end labeling (TUNEL) assay. The immunohistochemistry stain and enzyme linked immunosorbent assay (ELISA) was used to determine the expressions of caspase-3 and PARP in brain tissue. The results indicated that rats in the control group showed neurological function deficit and cerebral infarction in ischemic hemisphere after two hours ischemia followed by 22 hours reperfusion. Caspase-3 and PARP expressions were also profound in the cortex, the striatum and the hippocampus, along with increased apoptotic cells in this group. Bederson's score, infarction volume, and expressions of caspase-3 and PARP, as well as apoptosis in the treatment group were, however, significantly decreased compared to those in the control group indicating that intravenous treatment with picroside II might be beneficial to inhibit neuronal apoptosis and, thus, to improve the neurological function of rats upon cerebral ischemia reperfusion injury.

A methanol extract of rhizomes of Picrorhiza kurroa Royle ex Benth. (Plantaginaceae) showed hepatoprotective effects against D-galactosamine (D-GalN)/lipopolysaccharide (LPS)-induced liver injury in mice. We had previously isolated 46 compounds, including several types of iridoid glycosides, phenylethanoid glycosides, and aromatics, etc., from the extract. Among them, picroside II, androsin, and 4-hydroxy-3-methoxyacetophenone exhibited active hepatoprotective effects at doses of 50-100 mg/kg, per os (p.o.) To characterize the mechanisms of action of these isolates and to clarify the structural requirements of phenylethanoid glycosides for their hepatoprotective effects, their effects were assessed in in vitro studies on (i) D-GalN-induced cytotoxicity in mouse primary hepatocytes, (ii) LPS-induced nitric oxide (NO) production in mouse peritoneal macrophages, and (iii) tumor necrosis factor-α (TNF-α)-induced cytotoxicity in L929 cells. These isolates decreased the cytotoxicity caused by D-GalN without inhibiting LPS-induced macrophage activation and also reduced the sensitivity of hepatocytes to TNF-α. In addition, the structural requirements of phenylethanoids for the protective effects of D-GalN-induced cytotoxicity in mouse primary hepatocytes were evaluated.

Picroside II, a bioactive compound isolated from Picrorhiza scrophulariiflora Pennell, has been reported to have hepatoprotective, neuroprotective, and antioxidant effects. However, the detailed in vivo biotransformation of this compound has been rarely reported. This study aimed to investigate the metabolic profiles of picroside II in rats by using ultra-high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry. Metabolite structures were elucidated based on accurate mass measurements of deprotonated molecules and their fragmentation patterns. Thirteen metabolites were structurally identified, and the detailed metabolic pathways were proposed. The findings revealed that after oral administration, picroside II mainly undergoes four metabolic pathways. In the first pathway, picroside II is deglycosylated to generate aglycone, which is isomerized to a dialdehyde-type intermediate. A series of metabolic reactions, including glucuronidation, subsequently occurs. In the second pathway, picroside II is subjected to ester bond hydrolysis to form vanillic acid, which is further subjected to sulfate conjugation, glycine conjugation, glucuronidation, and demethylation. In the third pathway, picroside II is directly conjugated with glucuronic acid to yield a predominant metabolite (M01) in plasma. In the fourth pathway, picroside II is directly conjugated with sulfate. These findings provide insights into the in vivo disposition of picroside II and are useful to understand the mechanism of effectiveness and toxicity of this compound as well as P. scrophulariiflora -related preparations. [ABSTRACT FROM AUTHOR]

A novel voltammetric sensor was constructed by simple dripping single-walled carbon nanotubes (SWCNTs) on to the glass carbon electrode (GCE) firstly and electro-polymerizing l -Citrulline film subsequently. The resulting poly( l -Citrulline)/SWCNTs/GCE showed a significant voltammetric response to picroside II due to the synergistic effect of SWCNTs and poly( l -Citrulline) film. The first electroanalytical method of picroside II was proposed with detection linear range from 8.0×10 −8 to 5.0×10 −6 mol L −1 and a detection limit of 3×10 −8 mol L −1 .The high sensitivity, selectivity and long-term stability made the sensor suitable for the determination of picroside II. Moreover, based on the systematically investigation and some kinetics parameters calculated in the experimentation, the reaction mechanism of picroside II at the poly( l -Citrulline)/SWCNTs modified GCE was obtained reliably. Lastly, the proposed sensor was used for the determination of picroside II in real sample with satisfactory results. This work promoted the potential applications of amino acid materials and SWCNTs in electro-chemical sensors. [ABSTRACT FROM AUTHOR]

The objective of this study is to explore the neuroprotective effect and mechanism of picroside II on ERK1/2-COX2 signal transduction pathway after cerebral ischemic injury in rats. Focal cerebral ischemic models were established by inserting monofilament threads into the middle cerebral artery in 200 Wistar rats. Twenty four rats were randomly selected into control group, while the other rats were randomly divided into six groups: model group, picroside group, lipopolysaccharide (LPS) with picroside group, U0126 with picroside group, LPS group, and U0126 group with each group containing three subgroups with ischemia at 6, 12, and 24 h. Neurobehavioral function in the rats was evaluated by modified neurological severity score points (mNSS) test; structure of neurons was observed using hematoxylin-eosin (HE) staining; apoptotic cells were counted using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay; expressions of phosphorylated mitogen/extracellular signal-regulated kinase kinas1/2 (pMEK1/2), phosphorylated extracellular signal-regulated protein kinase1/2 (pERK1/2), and cyclooxygenase (COX2) in the cortex were determined using immunohistochemistry (IHC) and Western blot (WB); and real-time PCR was used to determine the level of COX2 mRNA. The neurological behavioral malfunction appeared in all rats with middle cerebral artery occlusion (MCAO). In the model group, neuron damage was extensive, while the neurobehavioral function score, apoptotic cell index, expression of pMEK1/2, pERK1/2, and COX2 and the level of COX2 mRNA increased significantly when compared to the control group. The peak COX2 mRNA level was in ischemia 12 h, prior to the peak in COX2 protein expression. In the picroside and U0126 groups, the neurological behavioral function was improved, and the number of apoptotic cells and the expression of pMEK1/2, pERK1/2, and COX2 decreased significantly when compared to the model group. In the LPS with picroside group, at ischemia 6 h neuron damage was extensive, and pMEK1/2, pERK1/2, and COX2 expression were much higher than in the model group. But at ischemia 12 and 24 h, the expression of pMEK1/2, pERK1/2, and COX2 decreased slightly, and the neurobehavioral function also improved slightly. In LPS group, neuron damage was extensive, pMEK1/2, pERK1/2, and COX2 expression was still at a high level, and COX2 mRNA peak arrived at ischemic 12 h. Picroside II downregulates COX2 expression after MCAO by inhibiting MEK-ERK1/2 in rats to protect neurons from apoptosis and inflammation. [ABSTRACT FROM AUTHOR]

In the study, the neuroprotective effect and underlying mechanism of picroside II were explored, and its involvement in the ERK1/2 signal pathway after cerebral ischemia injury in rats. A monofilament thread was inserted to generate middle cerebral artery occlusion ( MCAO) in 100 Wistar rats that were administered an intraperitoneal injection of picroside II (20 mg/kg). The neurobehavioural function of rats was evaluated using a modified neurological severity score ( mNSS) test. The cerebral infarct volume ( CIV) was measured using tetrazolium chloride ( TTC) staining. The morphology and ultra-structure of the nerve cells in the cortex were observed using hematoxylin and eosin ( HE) staining and transmission electron microscopy ( TEM), respectively. The apoptotic cells were counted using the terminal deoxynucleotidyl transferase dUTP nick end labeling ( TUNEL) assay. The expression of extracellular signal-regulated kinase 1/2 ( pERK1/2) in the cortex was determined using immunohistochemistry and Western blot analysis. Neurological dysfunction was observed in all rats with MCAO. In both the model and lipopolysaccharide ( LPS) groups, the CIV increased, the neuronal damage in the cortex was more severe, and the number of apoptotic cells and the pERK1/2 expression significantly increased compared with the control group ( P < 0.05). In treatment and U0126 groups, the neurological function was improved, the CIV decreased, the neuronal damage in the cortex was attenuated, and the number of apoptotic cells and the pERK1/2 expression significantly decreased compared with the model group ( P < 0.05). No significant differences in these indices were observed between model and LPS groups or treatment and U0126 groups ( P > 0.05). The results suggest that activation of ERK1/2 in cerebral ischaemia induces neuronal apoptosis and picroside II may reduce neuronal apoptosis to confer protection against cerebral ischemic injury by inhibiting ERK1/2 activation. [ABSTRACT FROM AUTHOR]

Picroside II possesses a wide range of pharmacological effects and has been demonstrated to ameliorate cerebral ischemia and reperfusion (I/R) injury. However, its effects on renal I/R injury remain unclear. In the present study, the role of picroside II in attenuating oxidative stress and the inflammatory response in a rat model of renal I/R injury was investigated. Sprague Dawley rats were subjected to 45 min of ischemia followed by 24 h of reperfusion. Prior to reperfusion, the rats were treated with picroside II or an equal volume of phosphate-buffered saline. Renal function and histological changes were compared and the relevant parameters of oxidative stress and inflammation were detected. The expression of toll-like receptor 4 (TLR4) and nuclear factor κB (NF-κB; p65) were assessed by immunohistochemistry and western blotting. It was observed that renal function was significantly improved by treatment with picroside II. Morphological analysis indicated that picroside II clearly reduced tissue damage and the expression of TLR4 and NF-κB. Reverse transcription-quantitative polymerase chain reaction demonstrated that picroside II inhibited the increase of tumor necrosis factor (TNF)-α, interleukin (IL)-1β and intercellular adhesion molecule (ICAM)-1 expression induced by I/R injury. Western blot analysis indicated that the expression levels of TLR4 and NF-κB were significantly downregulated in the picroside II group compared with those in the I/R group. These results indicate that picroside II treatment suppressed the TLR4/NF-κB signaling pathway, protecting renal tissue against I/R-induced oxidative stress and inflammatory response. [ABSTRACT FROM AUTHOR]

Renal ischemia and reperfusion (I/R) injury, which commonly occurs in kidney transplantation, is the leading cause of acute kidney injury. Picroside II possesses a wide range of pharmacological effects, including anti-apoptosis effects. In the present study, the ability of picroside II to attenuate apoptosis in a rat model of renal I/R injury was investigated. Sprague-Dawley rats were subjected to 45 min of ischemia followed by 24 h of reperfusion. Prior to reperfusion, the rats were treated with picroside II or an equal volume of phosphate-buffered saline. It was observed that renal function was significantly improved by the treatment with picroside II. Morphological analysis indicated that picroside II markedly reduced tissue damage and the expression of cleaved caspase-3. Reverse transcription-quantitative polymerase chain reaction and western blotting revealed that the expression levels of Bax and poly(ADP-ribose) polymerase-1 (PARP-1) were upregulated in the I/R group, whereas those of Bcl-2 were downregulated. However, the treatment with picroside II inhibited these changes induced by renal I/R injury. In conclusion, picroside II has potent anti-apoptotic activity against renal I/R injury. [ABSTRACT FROM AUTHOR]

The response surface methodology was employed to study the optimization of microwave-assisted extraction of picroside I and picroside II from Picrorrhiza kurroa Royle rhizomes. The effects of solid to solvent ratio, and extraction temperature, time and solvent on the yields of picroside I and picroside II have been investigated using Box-Behnken experimental design. The experimental data were fitted to second-order polynomial equations using multiple regression analysis and analyzed using the appropriate statistical method. By solving the regression equation and analyzing 3-D plots, the optimum extraction conditions were found to be: solid to solvent ratio, 10: 90 (w/v); temperature, 60 °C; and extraction time, 60 s. Under the optimal conditions, the yields of picroside I and picroside II are 41.23 and 6.12 mg·g feed respectively, which are in good agreement with the predicted values. The ratio of solid to solvent significantly affects the yields of picroside I and picroside II. Application of microwaveassisted extraction of picroside I and picroside II from P. kurroa would dramatically reduce extraction time and solvent consumption. [ABSTRACT FROM AUTHOR]

In kidney transplantation, renal ischemia and reperfusion injury was one of the leading factors to the development of renal fibrosis, which was the main cause of graft loss. The fibrogenic changes were associated with the long term inflammation elicited by ischemia and reperfusion injury. In the present study, we investigated the role of the Picroside II, the main active constituents of the extract of picrorrhiza scrophulariiflora roots, in attenuating renal fibrosis in a renal ischemia and reperfusion injury model. We induced ischemia and reperfusion injury in kidneys treated with or without Picroside II. We observed that inflammation and tissue fibrosis were increased in ischemia and reperfusion injury group compared to Picroside II group, however, these changes were significantly decreased by the treatment with Picroside II. We concluded that Picroside II can protect the ischemic kidney against renal fibrosis and its mechanism may be through the inhibition of the long term inflammation. [ABSTRACT FROM AUTHOR]

Background To explore the neuroprotective effect and optimize the therapeutic dose and time window of picroside II by orthogonal test and the expression of myelin basic protein (MBP) in cerebral ischemic injury in rats. Bilateral common carotid artery occlusion (BCCAO) was used to establish forebrain ischemia models. The successful rat models were grouped according to orthogonal experimental design and injected picroside II intraperitoneally at different ischemic time with different doses. Myelin sheath fast green staining(FGS) and transmission electron microscopy (TEM) were used to observe nerve fiber myelin; the expression of MBP was tested qualitatively and quantitatively by immunohistochemical assay (IHC) and Western blot (WB); Reverse transcription polymerase chain reaction (RT-PCR) was used to detect the transcription level of MBP mRNA. Results The protective effect of picroside II was presented by increasing the expression of MBP and decreasing demyelination after cerebral ischemic injury. The best therapeutic time window and dose was (1) ischemia 2.0 h with picroside II 10 mg/kg body weight according to the results of FGS, IHC and WB; (2) ischemia 1.5 h with picroside II 20 mg/kg according to the analysis of RT-PCR. Conclusion Given the principle of the longest time window and the lowest therapeutic dose, the optimized therapeutic dose and time window should be injecting picroside II intraperitoneally with 10-20 mg/kg body weight at ischemia 1.5-2.0 h in cerebral ischemic injury. [ABSTRACT FROM AUTHOR]

Abstract: Picrosides I and II are the active chemical constituents, present in the roots and rhizomes of Picrorhiza kurroa Royle (family: Scrophulariaceae). The plant is ethnomedically claimed for the treatment of liver and upper respiratory tract infection, fever, dyspepsia and scorpion sting. This study attempts to determine the in vivo pharmacokinetic profile of picrosides I and II in rats after oral administration of three different preparations namely, kutkin (a mixture of picrosides I and II), P. kurroa extract and Picrolax® capsule (marketed formulation). A simple, precise, specific and sensitive method was developed for simultaneous quantification of picrosides I and II in rat plasma and was applied for the pharmacokinetic study. Pharmacokinetic parameters were calculated from the observed plasma concentration of picrosides I and II. The results showed a significant difference (p≤0.05) in oral bioavailability of picrosides I and II from different preparations. Both the compounds were found to be more bioavailable from P. kurroa extract followed by Picrolax® capsule and kutkin. Moreover, we also developed a novel method for isolation of kutkin from roots of P. kurroa with a high yield of 2.4% w/w. The information gained from this study provides a meaningful basis for clinical application and mechanistic study of such phytochemicals. [Copyright &y& Elsevier]

ABSTRACT Introduction Picroside I and picroside II have been studied intensively because of their pharmacological actions and clinical applications. Numerous methods have been reported for extracting picroside I and picroside II from Picrorrhiza. kurroa rhizomes. This is the first report of picroside I and picroside II extraction using the supercritical carbon dioxide assisted extraction technique. Objective To develop supercritical carbon dioxide assisted extraction and LC-MS identification of picroside I and picroside II from the Picrorrhiza kurroa Royle rhizomes. Methodology Surface response methodology based on 33 fractional factorial design was used to extract picroside I and picroside II from P. kurroa rhizomes. The effects of various process factors, namely temperature (40-80°C), pressure (25-35 MPa) and co-solvent (methanol) concentration (0-10% v/v) on extraction yield of the two compounds were evaluated. The picroside I and picroside II contents were determined using validated LC-MS methodology. Results The maximum yield of picroside I (32.502 ± 1.131 mg/g) and picroside II (9.717 ± 0.382 mg/g) was obtained at the 10% v/v co-solvent concentration, 40°C temperature and 30 MPa pressure. The conventional Soxhlet assisted methanol extract of P. kurroa powder resulted in 36.743 ± 1.75 and 11.251 ± 0.54 mg/g yield of picroside I and picroside II, respectively. Conclusion Variation of concentration and extraction time showed a significant effect on the picroside I and picroside II yield. Supercritical carbon dioxide assisted extraction using methanol as a co-solvent is an efficient and environmentally sustainable method for extracting picroside I and picroside II from P. kurroa rhizomes. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Context: Picroside II, an iridoid glucoside found in the root of Picrorhiza scrophulariiflora Pennell (Scrophulariaceae), has been demonstrated to possess potent antioxidant activity. However, whether picroside II has a protective effect against hypoxia/reoxygenation (H/R)-induced cardiomyocyte injury is poorly understood. Objective: To explore the cardioprotective role of picroside II against oxidative stress induced by H/R injury in neonatal rat cardiacmyocytes. Materials and methods: The viability and cellular damage of cardiomyocytes were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolim bromide (MTT) and lactate dehydrogenase (LDH) assays, respectively. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), the levels of reduced (GSH) and oxidized glutathione (GSSG), and the contents of malondialdehyde (MDA) were determined by a colorimetric method. The levels of intracellular reactive oxygen species (ROS) and calcium were evaluated by flow cytometric analysis. Results: We analyzed the effective half-maximal concentration for protection from the dose-response curves and obtained the concentration of 50 µg/mL as EC50. Pretreated cardiomyocytes with picroside II (50-200 µg/mL), prior to H/R exposure, inhibited LDH activity in culture media and increased cell viability in a dose-dependent manner. This protective effect was accompanied by significantly increasing reduced GSH contents and the activities of SOD and GSH-Px and attenuating MDA and GSSG contents in response to H/R injury. Furthermore, treatment with picroside II also inhibited ROS production and calcium accumulation in cardiomyocytes. Discussion and conclusion: The present study demonstrates that picroside II protects cardiomyocytes against oxidative-stress injury induced by H/R through reduction of ROS production and calcium accumulation and enhancement of the activity of antioxidant defense. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore the optimal therapeutic dose and time window of picroside II for treating cerebral ischemic injury in rats according to the orthogonal test. The middle cerebral artery occlusion (MCAO) models were established by intraluminally inserting a thread into middle cerebral artery (MCA) from left external carotid artery (ECA). The successful rat models were randomly divided into 16 groups according to the orthogonal layout of [L16(45)] and treated by injecting picroside II intraperitoneally with different doses at various times. The neurological behavioral function was evaluated by Bederson's test and the cerebral infarction volume was measured by tetrazolium chloride (TTC) staining. The expressions of neuron specific enolase (NSE) and neuroglial mark-protein S-100 were determined by immunohistochemisty assay. The results indicated that the optimal compositions of the therapeutic dose and time window of picroside II in treating cerebral ischemic injury were ischemia 1.5 h with 20 mg/kg body weight according to Bederson's test, 1.0 h with 20 mg/kg body weight according to cerebral infarction volume, 1.5 h with 20 mg/kg body weight according to the expressions of NSE and S-100 respectively. Based on the principle of the minimization of medication dose and maximization of therapeutic time window, the optimal composition of the therapeutic dose and time window of picroside II in treating cerebral ischemic injury should be achieved by injecting picroside II intraperitoneally with 20 mg/kg body weight at ischemia 1.5 h. [ABSTRACT FROM AUTHOR]

Picrorhiza kurrooa Royle ex Benth (Scrophulariaceae), commonly known as Kutki, is a major ingredient of many ayurvedic preparations prescribed in the treatment of various diseases. Picrosides I and II are the active agents responsible for the medicinal effects of Kutki, and the variation in content of these compounds in plants at different altitudes is a major question to be addressed. The picroside I and II content in various plant parts of P. kurrooa collected from different altitudes, viz. Sonemarg (2,740 m a.s.l.), Tangmarg (2,690 m a.s.l.), and Pulwama (1,630 m a.s.l.) in the north-western Kashmir Himalayas was analyzed by HPLC. A considerable degree of variation in picroside content was observed. Picroside I and II was highest in populations collected from Sonemarg followed by Tangmarg, suggesting that picroside accumulation is directly correlated with altitudinal change. More picroside I was found in the rhizome and roots of the Pulwama population as compared to Tangmarg samples, whereas the quantity of Picroside II was reduced in plants from Pulwama compared to the Tangmarg population, suggesting that cultivation of P. kurroa at lower altitude reduces the picroside content. The quantities of picrosides also varied spatially, being highest in rhizome followed by roots, inflorescence and leaves in the populations from all three locations. The study concludes that picroside I and II accumulation depends on altitude, which could help in the selection and collection of superior genotypes with uniform effects for utilization by the pharmaceutical industry. [ABSTRACT FROM AUTHOR]

Picroside II is one of the main active constituents of Picrorhiza kurroa, which has hepatoprotective, anticholestatic, antioxidant, and immune-modulating activity. To gain an understanding of the biotransformation of picroside II in vivo, liquid chromatography -electrospray ionization ion-trap mass spectrometry (LC-ESI-IT-MS) was used to investigate the metabolism of picroside II in rats after intravenous administration of a single dose. This method could simultaneously determine picroside II and its metabolites in rat bile. The bile samples were purified by use of a C solid-phase extraction (SPE) cartridge and were separated on a Hypersil ODS2 C analytical column. Two phase II metabolites of picroside II in rat bile were characterized, and elucidation of their structures was performed by comparing changes in molecular masses (Δ M), retention times, and MS spectral patterns of metabolites with those of the parent drug. Two metabolites identified for the first time in this research were glucuronide and sulfate conjugates. [ABSTRACT FROM AUTHOR]

The article presents an in vivo study regarding the anti-oxidant effect of picroside II, an active component extracted from the rhizome and roots of Picrorhiza kurroa, in rats with cerebral ischemia/reperfusion injuries. The study used enzyme-linked immunosorbent assay and immunohistochemistry. Results showed that picroside II exhibited a neuroprotective effect by inhibiting neuronal apoptosis and downregulating inducible nitric oxide synthase expression.

The aim of this study was to explore the effect of picroside II on neuronal apoptosis and the expression of caspase-3 and poly ADP-ribose polymerase (PARP) following middle cerebral artery occlusion/reperfusion in male Wistar rats. Picroside II (10 mg/kg) was administered intravenously into the tail vein of the animals. The neurological function deficits were evaluated with the Bederson's test and the cerebral infarction volume was visualized with tetrazolium chloride (TTC) staining. The apoptotic cells were counted by in situ terminal deoxynucleotidyl transferase-mediated biotinylated deoxyuridine triphosphate nick end labeling (TUNEL) assay. The immunohistochemistry stain and enzyme linked immunosorbent assay (ELISA) was used to determine the expressions of caspase-3 and PARP in brain tissue. The results indicated that rats in the control group showed neurological function deficit and cerebral infarction in ischemic hemisphere after two hours ischemia followed by 22 hours reperfusion. Caspase-3 and PARP expressions were also profound in the cortex, the striatum and the hippocampus, along with increased apoptotic cells in this group. Bederson's score, infarction volume, and expressions of caspase-3 and PARP, as well as apoptosis in the treatment group were, however, significantly decreased compared to those in the control group indicating that intravenous treatment with picroside II might be beneficial to inhibit neuronal apoptosis and, thus, to improve the neurological function of rats upon cerebral ischemia reperfusion injury. [ABSTRACT FROM AUTHOR]

ABSTRACT: AIM: To evaluate the effects of picroside II on P450 activities in rats. METHODS: Five probe drugs (diclofenac, midazolam, dextromethorphan, chlorzoxazone and omeprazole) were simultaneously given to rats after single and multiple dosing of picroside II. The plasma concentrations of the five probes were measured by LC-MS and their corresponding pharmacokinetic parameters were calculated. RESULTS: There were no differences among the five probes in their plasma concentrations and the corresponding pharmacokinetic parameters in rats after single dosing of picroside II (10 mg·kg−1). The AUC0-t and the drug concentration of omeprazole increased significantly (P< 0.05) in rats after multiple dosing of picroside II (10 mg·kg−1, orally, twice daily for 12 consecutive days). CONCLUSION: Single administration of picroside II had very little impact on the activities of P450 while multiple administration of picroside II tended to inhibit CYP2C19 activity. [Copyright &y& Elsevier]