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Functional impairments in the brain's insulin and insulin-like growth factor (IGF) signal transduction networks are recognized mediators of dysregulated energy metabolism, a major driver of the Alzheimer's disease (AD) neurodegeneration cascade. AD-associated insulin-deficient and insulin-resistant states mimic those of diabetes mellitus and affect all cell types in the brain. Besides accounting for abundant amyloid-β and hyperphosphorylated tau lesions in AD, insulin/IGF pathway dysfunctions cause cortical atrophy, loss of synaptic plasticity, white matter myelin/oligodendrocyte degeneration, astrocyte and microglial neuroinflammation and oxidative stress, deficits in energy metabolism, mitochondrial dysfunction, and microvascular disease. These same neuropathological processes have been linked to cognitive impairment in type 2 diabetes mellitus, Parkinson's disease, and vascular dementia. Strategies to address metabolic mediators of cognitive impairment have been borrowed from diabetes and other insulin-resistant diseases and leveraged on preclinical AD model data. The repurposing of diabetes drugs led to clinical trials with intranasal insulin, followed by insulin sensitizers including metformin and peroxisome-proliferator-activated receptor agonists, and then incretin mimetics primarily targeting GLP-1 receptors. In addition, other glucose-lowering agents have been tested for their efficacy in preventing cognitive declines. The strengths and limitations of these approaches are discussed. The main conclusion of this review is that we have now arrived at a stage in which it is time to address long-term deficits in trophic factor availability and receptor responsiveness, signaling abnormalities that extend beyond insulin and include IGFs and interconnected pathways, and the need for multi-pronged rather than single-pronged therapeutic targeting to remediate AD and other forms of neurodegeneration. [ABSTRACT FROM AUTHOR]

Background and Purpose: Insulin therapies for Type 1 diabetes (T1D) have limitations, such as glucose fluctuations, hypoglycaemia, and weight gain. Only pramlintide is approved with insulin. However, its short half‐life limits efficacy, requiring multiple daily injections and increasing hypoglycaemia risk. New strategies are needed to improve glycaemic control. Dual amylin and calcitonin receptor agonists are potent insulin sensitizers developed for Type 2 diabetes (T2D) as they improve glucose control, reduce body weight, and attenuate hyperglucagonemia. However, it is uncertain if they could be used to treat T1D. Experimental Approach: Sprague Dawley rats received a single intravenous injection of streptozotocin (STZ) (50 mg·kg−1) to induce T1D. Humulin (1 U/200 g·day−1 or 2 U/200 g·day−1) was continuously infused, while half of the rats received additional KBP‐336 (4.5 nmol·kg−1 Q3D) treatment. Bodyweight, food intake, and blood glucose were monitored throughout the study. An oral glucose tolerance test was performed during the study. Key Results: Treatment with Humulin or Humulin + KBP‐336 improved the health of STZ rats. Humulin increased body weight in STZ rats, but KBP‐336 attenuated these increases and maintained a significant weight loss. The combination exhibited greater blood glucose reductions than Humulin‐treated rats alone, reflected by improved HbA1c levels and glucose control. The combination prevented hyperglucagonemia, reduced amylin levels, and increased pancreatic insulin content, indicating improved insulin sensitivity and beta‐cell preservation. Conclusion and Implications: The insulin sensitizer KBP‐336 lowered glucagon secretion while attenuating insulin‐induced weight gain. Additionally, KBP‐336 may prevent hypoglycaemia and improve insulin resistance, which could be a significant advantage for individuals with T1D seeking therapeutic benefits. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of insulin sensitizer rosiglitazone on blood METRNL levels. Methods After fed with high fat diet (HFD) for 3 months, obese mice were treated with rosiglitazone for 1 month. Glucose tolerance was tested with glucose tolerance test (GTT), and METRNL levels in blood were measured by ELISA. Real time fluorescence quantitative PCR was used to detect the expression of METRNL in various tissues such as muscle, liver, white fat, brown fat, brain, spleen and kidney, as well as the expression of mitochondrial proteins in brown adipose tissue. Results Glucose tolerance of animals fed a high-fat diet was improved in rosiglitazone group, and blood METRNL levels were also increased significantly in this group. Rosiglitazone treatment increased the expression of METRNL in brown fat and kidney tissue. There was no effect on METRNL expression in muscle, liver, white fat, brain and spleen. Rosiglitazone increased the expression of mitochondrial-associated proteins in brown adipose tissue. Conclusion The insulin sensitizer rosiglitazone might increase the serum METRNL level by increasing the METRNL expression in brown fat and kidney tissue, suggesting that METRNL may be involved in the therapeutic effect of rosiglitazone on diabetes. [ABSTRACT FROM AUTHOR]

Introduction: Polycystic ovarian syndrome (PCOS) is the commonest cause of infertility due to anovulation. The combination of Curcuma longa (CL) and Emblica officinalis (EO) is known to ameliorate diabetes and, thereby, may resurrect PCOS. The present study aimed to evaluate the effect of this combination prepared by two different methods, independently and with metformin (Met), compared with Met in PCOS on glycaemic control, inflammation, adipokines, and anthropometry. Aim: The aim of the study was to evaluate the effect of the combination of CL and EO, prepared by two different methods, independently and with Met, compared with Met in PCOS. Materials and Methods: PCOS women aged 18–35 years were selected through Rotterdam criteria from a tertiary care teaching hospital setting post-Ethics Committee permission. They were randomized to five groups (eight per group); combination of CL and EO prepared by traditional method (TF- Traditional Formulation), standardized extraction method (PNAE- Pharmanza Nisha Amalaki Extract), standard control Metformin (Met) and their combinations, TF + Met and PNAE + Met for 90 days. Fasting glucose, insulin, lipid profile, reproductive hormones (luteinizing hormone [LH], follicle-stimulating hormone [FSH], and free testosterone), inflammatory markers (tumor necrosis factor-alpha [TNF-α], interleukin [IL]-6), and adipokines (leptin and adiponectin) were done at baseline and day 90, whereas anthropometry was done monthly. Results: Of 48 randomized women, 37 completed the study. TF and Met groups demonstrated higher weight decrease, whereas TF + Met significantly decreased waist circumference. Blood glucose, insulin, and homeostasis model assessment of insulin resistance (HOMA-IR) decreased in all groups except glucose in TF + Met and HOMA-IR in the Met group. Only PNAE decreased free testosterone. TNF-α increased while leptin decreased in all groups. Both TF and PNAE, with Met reduced IL 6, significantly only in PNAE + Met group. Similarly, both TF and PNAE, with Met reduced LH/FSH ratio and significantly increased adiponectin. Two females, each, conceived in TF and PNAE, whereas one was in PNAE + Met group. No adverse events were reported. Conclusion: Both botanical formulations, TF and PNAE, were comparable to Met. The standardized extracts formulation PNAE seems more promising due to administration ease, smaller dose, and consistent bioactives. [ABSTRACT FROM AUTHOR]

Introduction: Polycystic ovarian syndrome (PCOS) is the commonest cause of infertility due to anovulation. The combination of Curcuma longa (CL) and Emblica officinalis (EO) is known to ameliorate diabetes and, thereby, may resurrect PCOS. The present study aimed to evaluate the effect of this combination prepared by two different methods, independently and with metformin (Met), compared with Met in PCOS on glycaemic control, inflammation, adipokines, and anthropometry. Aim: The aim of the study was to evaluate the effect of the combination of CL and EO, prepared by two different methods, independently and with Met, compared with Met in PCOS. Materials and Methods: PCOS women aged 18–35 years were selected through Rotterdam criteria from a tertiary care teaching hospital setting post-Ethics Committee permission. They were randomized to five groups (eight per group); combination of CL and EO prepared by traditional method (TF- Traditional Formulation), standardized extraction method (PNAE- Pharmanza Nisha Amalaki Extract), standard control Metformin (M­et) and their combinations, TF + Met and PNAE + Met for 90 days. Fasting glucose, insulin, lipid profile, reproductive hormones (luteinizing hormone [LH], follicle-stimulating hormone [FSH], and free testosterone), inflammatory markers (tumor necrosis factor-alpha [TNF-α], interleukin [IL]-6), and adipokines (leptin and adiponectin) were done at baseline and day 90, whereas anthropometry was done monthly. Results: Of 48 randomized women, 37 completed the study. TF and Met groups demonstrated higher weight decrease, whereas TF + Met significantly decreased waist circumference. Blood glucose, insulin, and homeostasis model assessment of insulin resistance (HOMA-IR) decreased in all groups except glucose in TF + Met and HOMA-IR in the Met group. Only PNAE decreased free testosterone. TNF-α increased while leptin decreased in all groups. Both TF and PNAE, with Met reduced IL 6, significantly only in PNAE + Met group. Similarly, both TF and PNAE, with Met reduced LH/FSH ratio and significantly increased adiponectin. Two females, each, conceived in TF and PNAE, whereas one was in PNAE + Met group. No adverse events were reported. Conclusion: Both botanical formulations, TF and PNAE, were comparable to Met. The standardized extracts formulation PNAE seems more promising due to administration ease, smaller dose, and consistent bioactives.

Prateek Sharma,1 Jayachandran Nair,1 Anurag Sinh,1 Shivangi,1 Thirumurthy Velpandian,2 Ruchi Tripathi,1 Rajani Mathur1 1Department of Pharmacology, Delhi Institute of Pharmaceutical Science and Research, Delhi Pharmaceutical Sciences and Research University, New Delhi, 110017, India; 2Department of Ocular Pharmacology, Dr. R.P. Center for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, 110029, IndiaCorrespondence: Rajani Mathur, Department of Pharmacology, Delhi Institute of Pharmaceutical Science and Research, Delhi Pharmaceutical Sciences and Research University, Pushp Vihar, Sec III, New Delhi, 110017, India, Tel +91-011-29551490, Fax +91-011-29554503, Email mathurajani@gmail.comPurpose: Fructose is highly lipogenic, and its unhindered ingestion by children and adolescents is understood to induce hypertriglyceridemia and non-alcoholic fatty liver disease (ped-NAFLD) that is till date managed symptomatically or surgically. The aim of the present study was to investigate the potential of hydroethanolic extract of leaves of Guava (PG-HM) to suppress the alterations in the hepatic molecular signals due to unrestricted fructose (15%) drinking by growing rats.Methods: Weaned rats (4 weeks old) in control groups had ad libitum access to fructose drinking solution (15%) for four (4FDR) or eight (8FDR) weeks, ie, till puberty or early adulthood, respectively, while treatment groups (4PGR, 8PGR) additionally received PG-HM (500 mg/kg, po).Results: The PG-HM suppressed ped-NAFLD through hepatic signalling pathways of 1) leptin-insulin (Akt/FOX-O1/SREBP-1c), 2) hypoxia-inflammation (HIF-1ɑ/VEGF, TNF-ɑ), 3) mitochondrial function (complexes I–V), 4) oxidative stress (MDA, GSH, SOD) and 5) glycolysis/gluconeogenesis/de novo lipogenesis (hexokinase, phosphofructokinase, ketohexokinase, aldehyde dehydrogenase). Parri passu, the insulin sensitizing effect of PG-HM and its ethyl acetate fraction (PG-EA) was elucidated using HepG2 cells grown in media enhanced with fructose. Further, in murine hepatocytes cultured in fructose-rich media, PG-HM (35 μg mL-1) outperformed Pioglitazone (15 μM) and Metformin (5 mM), to suppress hepatic insulin resistance.Conclusion: This study established that hydroethanolic extract of leaves of Guava (PG-HM) has potential to suppress hepatic metabolic alteration for the management of the pediatric NAFLD.Graphical Abstract: Keywords: Psidium guajava, pediatric NAFLD, insulin sensitizer, mitochondrial function

[Display omitted] Rosiglitazone, a full PPARγ agonist and a classical insulin sensitizer, was once used as a powerful weapon in the treatment of T2DM. However, its applications have been restricted recently because of its multiple side effects. Here, a natural compound, flavokawain B (FKB), which was screened in our previous experiments, was investigated for its potential as a preferable insulin sensitizer because it has no or few side effects. Using the surface plasmon resonance (SPR) technique, we confirmed that FKB is a natural ligand for PPARγ with high binding affinity. In in vitro experiments, FKB significantly increased 2-NBDG uptake in HepG2 and 3T3-L1 cells, which partially stimulated PPARγ transcriptional activity. Compared with rosiglitazone, FKB had little effect on the adipose differentiation of 3T3-L1 cells, and all of these features suggest that FKB is a selective modulator of PPARγ (SPPARγM). Moreover, FKB increased the mRNA expression levels of most genes related to insulin sensitivity and glucose metabolism but had no obvious effect on those related to adipose differentiation. In vivo experiments confirmed that FKB effectively decreased abnormal fasting blood glucose and postprandial blood glucose levels and reduced glycated hemoglobin levels, similar to rosiglitazone, in HFD-fed/STZ-treated and db/db mice, two T2DM animal models, but did not cause side effects, such as weight gain or liver or kidney damage. Further investigation revealed that FKB could inhibit PPARγ-Ser273 phosphorylation, which is the key mechanism involved in improving insulin resistance. Together, FKB is a well-performing SPPARγM that exerts a powerful glucose-lowering effect without causing the same side effects as rosiglitazone, and it may have great potential for development. [ABSTRACT FROM AUTHOR]

Cajanus cajan (L.) Millsp., known as pigeon pea, is one of the major grain legume crops of the tropical world. It recognizes as an ethnomedicine to possess various functions, such as helping in healing wound and cancer therapy. We investigated whether 95% ethanol extracts from C. cajan root (EECR) protect against methylglyoxal (MGO)-induced insulin resistance (IR) and hyperlipidemia in male Wistar rats and explored its possible mechanisms. The hypoglycemic potential of EECR was evaluated using α-amylase, α-glucosidase activities, and advanced glycation end products (AGEs) formation. For in vivo study, the rats were divided into six groups and orally supplemented with MGO except for Group 1 (controls). Group 2 was supplemented with MGO only, Group 3: MGO + metformin, Group 4: MGO + Low dose-EECR (L-EECR; 10 mg/kg bw), Group 5: MGO + Middle dose-EECR (M-EECR; 50 mg/kg bw), and Group 6: MGO + High dose-EECR (H-EECR; 100 mg/kg bw). EECR possessed good inhibition of α-glucosidase, α-amylase activities, and AGEs formation (IC50 = 0.12, 0.32, and 0.50 mg/mL), respectively. MGO significantly increased serum levels of blood glucose (GLU), glycosylated hemoglobin, homeostasis model assessment of IR, AGEs, lipid biochemical values, and atherogenic index, whereas EECR decreased these levels in a dose-dependent manner. EECR can also act as an insulin sensitizer, which significantly decreased (47%, P < 0.05) the blood GLU levels after intraperitoneal injection of insulin in the insulin tolerance tests. The hypoglycemic and antihyperlipidemic mechanisms of EECR are likely through several possible pathways including the inhibition of carbohydrate-hydrolyzing enzymes (α-glucosidase and α-amylase) and the enhancement of MGO-trapping effects on inhibition of AGEs formation.

Background: Alcohol-related brain degeneration is linked to cognitive-motor deficits and impaired signaling through insulin/insulin-like growth factor type 1 (IGF-1)-Akt pathways that regulate cell survival, plasticity, metabolism, and homeostasis. In addition, ethanol inhibits Aspartyl-asparaginyl-β-hydroxylase (ASPH), a downstream target of insulin/IGF-1-Akt signaling and an activator of Notch networks. Previous studies have suggested that early treatment with insulin sensitizers or dietary soy could reduce or prevent the long-term adverse effects of chronic ethanol feeding. Objective: The goal of this study was to assess the effects of substituting soy isolate for casein to prevent or reduce ethanol's adverse effects on brain structure and function. Methods: Young adolescent male and female Long Evans were used in a 4-way model as follows: Control + Casein; Ethanol + Casein; Control + Soy; Ethanol + Soy; Control = 0% ethanol; Ethanol = 26% ethanol (caloric). Rats were fed isocaloric diets from 4 to 11 weeks of age. During the final experimental week, the Morris Water maze test was used to assess spatial learning (4 consecutive days), after which the brains were harvested to measure the temporal lobe expression of the total phospho-Akt pathway and downstream target proteins using multiplex bead-based enzyme-linked immunosorbent assays (ELISAs) and duplex ELISAs. Results: Ethanol inhibited spatial learning and reduced brain weight, insulin signaling through Akt, and the expression of ASPH when standard casein was provided as the protein source. The substitution of soy isolate for casein largely abrogated the adverse effects of chronic ethanol feeding. In contrast, Notch signaling protein expression was minimally altered by ethanol or soy isolate. Conclusions: These novel findings suggest that the insulin sensitizer properties of soy isolate may prevent some of the adverse effects that chronic ethanol exposure has on neurobehavioral function and insulin-regulated metabolic pathways in adolescent brains. [ABSTRACT FROM AUTHOR]

Background: The efficacy and safety of insulin sensitizer in Asians with non-alcoholic steatohepatitis (NASH) remain elusive. Aims: The double-blind, randomized, placebo-controlled trial was conducted aiming to investigate the efficacy and safety of pioglitazone in NASH patients. Methods: A total of 90 NASH patients (66 males, age = 44.1 ± 12.7 years) were prospectively randomized into oral pioglitazone 30 mg/day (Arm A) or placebo (Arm B) for 24 weeks. The primary endpoint was the efficacy of pioglitazone in reducing inflammation and liver fat at end-of-treatment (EOT). NASH resolution/improvement without fibrosis worsening was also evaluated. Results: At EOT, there was a significantly decline of alanine aminotransferase (86.9 ± 34.3 to 45.7 ± 35.8 IU/L, p = 0.003) level in Arm A patients. In intention-to-treat analysis among 66 patients who completed paired biopsies, The NAFLD activity score (NAS) of 30 Arm A patients significantly decreased from 4.27 ± 1.14 at baseline to 2.53 ± 1.63 at EOT (p < 0.0001), whereas there was no significant change in patients of Arm B (3.94 ± 1.41 vs 3.94 ± 1.51, p = 1.0). NASH improvement without worsening of fibrosis was achieved in 46.7% (14/30) patients in Arm A, compared to 11.1% (4/36) patients in Arm B (p = 0.002). Liver fat content reduced (20.2 ± 9.0 to 14.3 ± 6.9%, p < 0.0001) on MRI–PDFF in Arm A compared to their counterparts. No significant difference of adverse events occurred between groups. Conclusions: A 24-week pioglitazone treatment was well-tolerated and effective in improving liver histology and reducing liver steatosis in Asian NASH patients. (ClinicalTrials.gov number: NCT01068444) [ABSTRACT FROM AUTHOR]

Insulin sensitizers, while effective in glucose-lowering for diabetes control, are linked to an increased risk of heart disease through mechanisms that are not well understood. In this study, we investigated the molecular mechanisms underlying the effects of insulin sensitization on cardiac sinus node dysfunction. We used pharmacologic or genetic approaches to enhance insulin sensitivity, by treating with pioglitazone or rosiglitazone, or through phosphatase and tensin homolog (PTEN) deletion in cardiomyocytes respectively. We employed an angiotensin II (Ang II)-induced hypertensive animal model which causes sinus node dysfunction and accumulation of oxidized calcium/calmodulin-dependent protein kinase II (CaMKII), which also serves as a biomarker for this defect. While neither PTEN deficiency nor insulin sensitizers caused sinus node dysfunction in normotensive mice, both accelerated the onset of sinus node dysfunction and CaMKII oxidation in hypertensive mice. These abnormalities were accompanied by a significant defect in autophagy as revealed by unc-51 like autophagy activating kinase 1 (ULK1) signaling. Indeed, mice deficient in ulk1 in cardiomyocytes and the sinus node also showed early onset of slow atrial impulse conduction with frequent sinus pauses and upregulated CaMKII oxidation following Ang II infusion similar to that seen with PTEN deficiency, or treatment with insulin sensitizers. To further elucidate the role of autophagy in sinus node dysfunction, we treated mice with a peptide D-Tat-beclin1 that enhanced autophagy, which significantly abrogated the frequent sinus pauses and accumulation of oxidized CaMKII induced by insulin sensitizers treatment, or PTEN deficiency in hypertensive animals. Together, these findings provide clear evidence of the detrimental cardiac effects of insulin sensitization that occurs through failure of autophagy-mediated proteolytic clearance. [ABSTRACT FROM AUTHOR]

Abstract Objective To evaluate the effect of insulin sensitizer on inflammatory cytokines and oxidative stress in patients with newly diagnosed type 2 diabetes mellitus (T2DM). Methods After intensive insulin therapy, patients with newly diagnosed T2DM were continuously treated with either insulin sensitizer or insulin for 48 weeks, and then their inflammatory cytokine and oxidative stress levels were measured. Results Tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, hypersensitive C reactive protein (hs-CRP), malondialdehyde (MDA), and 8-iso-prostaglandin F2α (8-iso-PGF2α) levels of the rosiglitazone (RSG) group and the rosiglitazone combined with metformin (RSG + metformin) group were significantly reduced after the treatments (P

Background: Alcohol-related brain degeneration is linked to cognitive-motor deficits and impaired signaling through insulin/insulin-like growth factor type 1 (IGF-1)-Akt pathways that regulate cell survival, plasticity, metabolism, and homeostasis. In addition, ethanol inhibits Aspartyl-asparaginyl-β-hydroxylase (ASPH), a downstream target of insulin/IGF-1-Akt signaling and an activator of Notch networks. Previous studies have suggested that early treatment with insulin sensitizers or dietary soy could reduce or prevent the long-term adverse effects of chronic ethanol feeding. Objective: The goal of this study was to assess the effects of substituting soy isolate for casein to prevent or reduce ethanol’s adverse effects on brain structure and function. Methods: Young adolescent male and female Long Evans were used in a 4-way model as follows: Control + Casein; Ethanol + Casein; Control + Soy; Ethanol + Soy; Control = 0% ethanol; Ethanol = 26% ethanol (caloric). Rats were fed isocaloric diets from 4 to 11 weeks of age. During the final experimental week, the Morris Water maze test was used to assess spatial learning (4 consecutive days), after which the brains were harvested to measure the temporal lobe expression of the total phospho-Akt pathway and downstream target proteins using multiplex bead-based enzyme-linked immunosorbent assays (ELISAs) and duplex ELISAs. Results: Ethanol inhibited spatial learning and reduced brain weight, insulin signaling through Akt, and the expression of ASPH when standard casein was provided as the protein source. The substitution of soy isolate for casein largely abrogated the adverse effects of chronic ethanol feeding. In contrast, Notch signaling protein expression was minimally altered by ethanol or soy isolate. Conclusions: These novel findings suggest that the insulin sensitizer properties of soy isolate may prevent some of the adverse effects that chronic ethanol exposure has on neurobehavioral function and insulin-regulated metabolic pathways in adolescent brains.

ObjectivesTo determine whether older women with diabetes mellitus have a greater longitudinal decline in physical performance than those without and whether any decline differs according to insulin sensitizer use.DesignProspective cohort study.SettingBaltimore, Maryland; Minneapolis, Minnesota; Portland, Oregon; and the Monongahela, Pennsylvania.ParticipantsCommunity-dwelling women (mean age 78.5 ± 3.6) enrolled in the Study of Osteoporotic Fractures in 1997-98 and restudied 4.9 ± 0.6 years later (N = 2,864).MeasurementsWomen were categorized as having no diabetes mellitus (n = 2,680) or having diabetes mellitus (n = 184). A prescription medication inventory was used to determine use of insulin sensitizers (metformin and thiazolidinedione). The outcomes were longitudinal changes in physical performance measures, including grip strength, usual walk speed, and rapid walk speed.ResultsEstimates from fully adjusted models showed that women with diabetes mellitus had greater declines in usual walk speed (-0.16 m/s, 95% confidence interval (CI) = -0.19 to -0.14) and rapid walk speed (-0.21 m/s, 95% CI = -0.24 to -0.17) than those without (usual walk speed -0.11 m/s, 95% CI = -0.12 to -0.11, P < .001; rapid walk speed -0.15 m/s, 95% CI = -0.16 to -0.14; P = .005). Women with diabetes mellitus taking insulin sensitizers had less decline in usual walk speed than those not taking insulin sensitizers (P < .001). Declines in grip strength did not differ significantly by diabetes mellitus status or insulin sensitizer use.ConclusionOlder women with diabetes mellitus have a greater decline in walk speed, but not grip strength, than older women without diabetes mellitus. Clinical studies in older adults to determine whether diabetes mellitus treatments such as insulin sensitizers can prevent loss in walk speed and mobility are needed.

Tangeretin, a flavonoid derived from citrus peel, showed anti-diabetic effects. However, the role of tangeretin on liver, the organ that act as target of insulin and play the central role in maintaining the blood glucose level control, is still largely unknown. The current study was designed to assess the effect of tangeretin on liver insulin sensitivity in vitro and in vivo. Primary hepatocytes and mice were treated with different dose of tangeretin, parameters of insulin sensitivity, such as blood glucose levels, serum insulin levels, glucose tolerate test (GTT), insulin tolerate test (ITT), insulin stimulated IR-AKT pathway were analyzed. Primary hepatocytes treated with 10/20 μM tangeretin showed up-regulated insulin signaling pathway as well as the glycogen content, while the glucose output were reduced. Intragastric administration of tangeretin (25/50 mg/kg) also ameliorated the liver insulin sensitivity and improved the glucose homeostasis, both in wild type C57 mice and in db/db mice, a diabetic model. Tangeretin treatment dose-dependently suppressed the MEK-ERK1/2 pathway, while forced activation of p -ERK1/2 reversed the insulin sensitized effect of tangeretin. These results indicated that tangeretin enhanced the liver insulin sensitivity in vitro and in vivo , through suppressing the MEK-ERK1/2 pathway. • Besides multiple reported organs, tangeretin targets liver to promote insulin sensitivity. • Tangeretin ameliorates insulin resistance and fatty liver in diabetic mice model. • Tangeretin promotes insulin sensitivity through blocking MEK-ERK1/2 pathway. [ABSTRACT FROM AUTHOR]

Insulin resistance is a common feature of many metabolic disorders. The dramatic rise in the incidence of insulin resistance over the past decade has enhanced focus on its developmental origins. Since various developmental insults ranging from maternal disease, stress, over/undernutrition, and exposure to environmental chemicals can all program the development of insulin resistance, common mechanisms may be involved. This review discusses the possibility that increases in maternal androgens associated with these various insults are key mediators in programming insulin resistance. Additionally, the intermediaries through which androgens misprogram tissue insulin sensitivity, such as changes in inflammatory, oxidative, and lip otoxic states, epigenetic, gut microbiome and insulin, as well as data gaps to be filled ar e also discussed. [ABSTRACT FROM AUTHOR]

The new substance element has been known as novel antidiabetic drug, eg: saroglitazar. saroglitazar is a medication used to treat type-2 diabetes. saroglitazar was known under the exchange name Lipaglyn, created by Zydus cadila. lipaglyn is the first drug approved to treat type- 2diabetes mellitus by the drug controller general of India in june 2013. Lipaglyn is demonstrated for the patients experiencing diabetes dyslipidaemia. It is given once daily for treatment. Saroglitazar manages the lipid parameters just as glycemic control. [ABSTRACT FROM AUTHOR]

Introduction: Current pharmacological treatments of post-traumatic stress disorder (PTSD) have limited efficacy. Although the diagnosis is based on psychopathological criteria, it is frequently accompanied by somatic comorbidities and perhaps "accelerated biological aging," suggesting widespread physical concomitants. Such physiological comorbidities may affect core PTSD symptoms but are rarely the focus of therapeutic trials.Methods: To elucidate the potential involvement of metabolism, inflammation, and mitochondrial function in PTSD, we integrate findings and mechanistic models from the DOD-sponsored "Systems Biology of PTSD Study" with previous data on these topics.Results: Data implicate inter-linked dysregulations in metabolism, inflammation, mitochondrial function, and perhaps the gut microbiome in PTSD. Several inadequately tested targets of pharmacological intervention are proposed, including insulin sensitizers, lipid regulators, anti-inflammatories, and mitochondrial biogenesis modulators.Conclusions: Systemic pathologies that are intricately involved in brain functioning and behavior may not only contribute to somatic comorbidities in PTSD, but may represent novel targets for treating core psychiatric symptoms. [ABSTRACT FROM AUTHOR]

Baicalein, a major component in Scutellaria baicalensis and Oroxylum indicum, is used as dietary supplement in Asia. In this study, we characterized the insulin-sensitizing activity of baicalein and found that baicalein improved insulin resistance by reducing the expression of SOCS3, increasing the phosphorylation of IRS1 and Akt1, reducing the phosphorylation of GSK3β and increasing hepatic glycogen level. We further evaluated the preventive effect of baicalein combined with acarbose in mice, aiming to enhance the therapeutic effect and reduce the side-effects of acarbose. The combination reduced the relative risk of progression from prediabetes to diabetes by 83.3% and the dose of acarbose by 80%. The underlying mechanisms include reducing postprandial hyperglycemia, improving insulin resistance, improving lipid metabolism, and reducing oxidative stress. Our results suggest that the consumption of 195–780 mg/d baicalein might improve the efficacy of acarbose on diabetes prevention and reduce the side-effects of acarbose in long-term acarbose users.

• Oral contraceptives induce dyslipidemia that should be routinely monitored. • Adding metformin to lifestyle modification accelerates weight loss in short term. • Benefits are limited from long-term addition of metformin to lifestyle modification. • Pharmacotherapies tailored based on baselines achieve more clinical improvements. Oral contraceptives (OCs), insulin sensitizers, and antiandrogens (AAs), alone or in combination, are commonly used for treating non-fertility indications in polycystic ovary syndrome (PCOS). However, unclear risk-benefit profiles jeopardize their appropriate clinical applications. This study aimed to quantitatively evaluate the effects of the aforementioned medications and to compare their risk-benefit profiles. Randomized controlled trials published until 14th March 2022 were searched in PubMed and Embase. A model-based meta-analysis was developed to examine the time-effect profiles of each medication. The maximal percentage change of the effect (E max) and time to achieve half of E max (T 50) were estimated. Primary outcomes included menstruation, hirsutism score, free androgen index (FAI), body mass index (BMI), insulin sensitivity, and lipid profiles. Overall, 200 studies (9,685 patients and 385 arms) were identified for modeling. OCs performed exceptionally well in improving menstruation (E max : 149%; T 50 : 7.44 weeks), hirsutism score (E max : 66.2%; T 50 : 26.2 weeks), and FAI (E max : 75.7%; T 50 : 0.51 weeks). However, OCs elevated the triglyceride (TG) level (E max : 12.6%; T 50 :1.19 weeks). After 12-week OC treatment, the TG level of approximately 30% of patients, whose baselines were normal, exceeded the reference limit. This suggested that OC-induced dyslipidemia should be routinely monitored. The maximal BMI-lowering effect of metformin was similar to that of placebo (E max : 3.80%); however, metformin had a shorter T 50 (6.67 weeks versus 12.9 weeks). Further, active lifestyle intervention plus placebo significantly decreased BMI (E max : 8.78%). Adding metformin to active lifestyle intervention accelerated the BMI-lowering effect within 24 weeks, whereas with the extension of this addition beyond 24 weeks, BMI did not reduce further, which indicated that benefits were limited from this prolonged addition. AAs were less potent in reducing hirsutism score (E max : 40.2% versus 66.2%) and FAI (E max : 34.5% versus 75.7%) compared to OCs. OC plus metformin combined OC-derived androgen-suppressing effects and metformin-derived insulin-sensitizing effects, and partially relieved the OC-induced TG increase (E max : 9.76%). Baseline dependency was found in most clinical responses, implying that pharmacotherapies tailored based on baselines achieved more clinical improvements. This study presents new quantitative evidence on pharmacotherapies for PCOS. Currently, long-term risk-benefit profiles and emerging therapies are inadequately reported and require more further research. [Display omitted] [ABSTRACT FROM AUTHOR]

Jing Sun,1 Xueqi Fu,1–3 Ye Liu,1 Yongsen Wang,1 Bo Huo,1 Yidi Guo,1 Xuefeng Gao,1 Wannan Li,1–3,* Xin Hu1–3,* 1School of Life Sciences, 2Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education, 3National Engineering Laboratory of AIDS Vaccine, School of Life Sciences, Jilin University, Changchun, People’s Republic of China *These authors contributed equally to this work Background: Honokiol is one of the main bioactive constituents of the traditional Chinese herbal drug Magnolia bark (Cortex Magnoliae officinalis, Hou Po). The aim of this study was to probe its anti-type 2 diabetes mellitus effects and the underlying mechanism.Methods: Type 2 diabetic mouse model was established by intraperitoneally injecting with streptozotocin. Fasting blood glucose, body weight, and lipid profile were measured. The subcutaneous adipose tissue, skeletal muscle, and liver were isolated as well as homogenized. The phospho-insulin receptor β-subunit (IRβ), IRβ, phospho-AKT, AKT, phospho-ERK1/2, ERK1/2, phosphotyrosine, and actin were examined by Western blot assay. Cell viability or cytotoxicity was analyzed by using MTT method. The inhibitory potencies of honokiol on the protein tyrosine phosphatase 1B (PTP1B) activity were performed in reaction buffer. Molecular docking and dynamic simulation were also analyzed.Results: In in vivo studies, oral treatment with 200 mg/kg honokiol for 8 weeks significantly decreases the fasting blood glucose in type 2 diabetes mellitus mice. The phosphorylations of the IRβ and the downstream insulin signaling factors including AKT and ERK1/2 significantly increase in adipose, skeletal muscle, and liver tissue of the honokiol-treated mice. Moreover, honokiol enhanced the insulin-stimulated phosphorylations of IRβ, AKT, and ERK1/2 in a dose-dependent manner in C2C12 myotube cells. Meanwhile, honokiol enhanced insulin-stimulated GLUT4 translocation. Importantly, honokiol exhibited reversible competitive inhibitory activity against PTP1B with good selectivity in vitro and in vivo. Furthermore, using molecular docking and dynamic simulation approaches, we determined the potential binding mode of honokiol to PTP1B at an atomic level.Conclusion: These findings indicated the hypoglycemic effects of honokiol and its mechanism that honokiol improved the insulin sensitivity by targeting PTP1B. Therefore, our study may highlight honokiol as a promising insulin sensitizer for the therapy of type 2 diabetes. Keywords: honokiol, T2DM, insulin sensitizer, PTP1B

Like in many developing countries, in Mexico, the use of medicinal plants is a common practice. Based on our own field experience, there are at least 800 plants used for treating diabetes nowadays. Thus, their investigation is essential. In this context, this work aims to provide a comprehensive and critical review of the molecules isolated from Mexican hypoglycemic plants, including their source and target tested. In the last few years, some researchers have focused on the study of Mexican hypoglycemic plants. Most works describe the hypoglycemic effect or the mechanism of action of the whole extract, as well as the phytochemical profile of the tested extract. Herein, we analyzed 85 studies encompassing 40 hypoglycemic plants and 86 active compounds belonging to different classes of natural products: 28 flavonoids, 25 aromatic compounds, other than flavonoids, four steroids, 23 terpenoids, 4 oligosaccharides, and 1 polyalcohol. These compounds have shown to inhibit α-glucosidases, increase insulin secretion levels, increase insulin sensitivity, and block hepatic glucose output. Almost half of these molecules are not common metabolites, with a narrow taxonomic distribution, which makes them more interesting as lead molecules. Altogether, this analysis provides a necessary inventory useful for future testing of these active molecules against different hypoglycemic targets, to get a better insight into the already described mechanisms, and overall, to contribute to the knowledge of Mexican medicinal plants.

BGP-15 is a new insulin sensitizer drug candidate, which was developed by Hungarian researchers. In recent years, numerous research groups have studied its beneficial effects. It is effective in the treatment of insulin resistance and it has protective effects in Duchenne muscular dystrophy, diastolic dysfunction, tachycardia, heart failure, and atrial fibrillation, and it can alleviate cardiotoxicity. BGP-15 exhibits chemoprotective properties in different cytostatic therapies, and has also proven to be photoprotective. It can additionally have advantageous effects in mitochondrial-stress-related diseases. Although the precise mechanism of the effect is still unknown to us, we know that the molecule is a PARP inhibitor, chaperone co-inducer, reduces ROS production, and is able to remodel the organization of cholesterol-rich membrane domains. In the following review, our aim was to summarize the investigated molecular mechanisms and pharmacological effects of this potential API. The main objective was to present the wide pharmacological potentials of this chemical agent.

The number of diabetic patients is rising globally and concomitantly so do the diabetes associated complications. The gut secretes a variety of proteins to control blood glucose levels and/or food intake. As the drug class of GLP-1 agonists is based on a gut secreted peptide and the positive metabolic effects of bariatric surgery are at least partially mediated by gut peptides, we were interested in other gut secreted proteins which have yet to be explored. In this respect we identified the gut secreted protein FAM3D by analyzing sequencing data from L- and epithelial cells of VSG and sham operated as well as chow and HFD fed mice. FAM3D was overexpressed in diet induced obese mice via an adeno-associated virus (AAV), which resulted in a significant improvement of fasting blood glucose levels, glucose tolerance and insulin sensitivity. The liver lipid deposition was reduced, and the steatosis morphology was improved. Hyperinsulinemic clamps indicated that FAM3D is a global insulin sensitizer and increases glucose uptake into various tissues. In conclusion, the current study demonstrated that FAM3D controls blood glucose levels by acting as an insulin sensitizing protein and improves hepatic lipid deposition., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

This systematic review investigated the effectiveness and safety of intensive insulin therapy (IIT), insulin secretagogues and sensitisers in burn patients. PubMed, Embase, clinicaltrials.gov and Cochrane central were searched from 1990 to 2016. Title/abstract screening, full-text review, critical appraisal and data extraction were carried out by two independent reviewers. Inclusion criteria were hospitalised burn patients, IIT, insulin sensitisers or secretagogues and the outcomes mortality, length of stay, resting energy expenditure, blood glucose, catabolism, or complications. We identified 594 potential studies of which 13 were included. Five studies investigated IIT in paediatric patients, 3 investigated IIT in adults and 5 investigated sensitisers or secretagogues. Glycaemic targets differed with age group - paediatric studies compared IIT to loose glycaemic control while adult studies compared IIT to more moderate control. Meta-analyses were limited by differences in outcome reporting, however mortality was increased in children by loose glycaemic control (OR=3.78, 95%CI 1.19-12.02) but not significantly affected in adults by moderate compared to tight control. Meta-analyses could not be performed for sensitisers or secretagogues. These findings support recommendations that moderate insulin administration (130-150mg/dL) is the prudent approach in burn patients. The evidence is relatively sparse and further research is warranted. [ABSTRACT FROM AUTHOR]

Prenatal testosterone (T)-treated female sheep manifest reduced adipocyte size and peripheral insulin resistance. The small adipocyte phenotype may reflect defects in adipogenesis and its steroidal machinery. To test whether prenatal T treatment from gestational days 30 to 90 alters the visceral adipose tissue (VAT) steroidal machinery and reduces adipocyte differentiation, we examined expression of the steroidogenic enzymes, steroid receptors, and adipocyte differentiation markers at fetal day 90 and postnatal ages 10 and 21 months. Because gestational T treatment increases fetal T and maternal insulin, the contributions of these were assessed by androgen receptor antagonist or insulin sensitizer cotreatment, either separately (at fetal day 90 and 21 months of age time points) or together (10 months of age). The effects on adipogenesis were assessed in the VAT-derived mesenchymal stem cells (AT-MSCs) from pre- and postpubertal time points to evaluate the effects of pubertal steroidal changes on adipogenesis. Our results show that VAT manifests potentially a predominant estrogenic intracrine milieu (increased aromatase and estrogen receptor α) and reduced differentiation markers at fetal day 90 and postnatal 21 months of age. These changes appear to involve both androgenic and metabolic pathways. Preliminary findings suggest that prenatal T treatment reduces adipogenesis, decreases expression of differentiation, and increases expression of commitment markers at both pre- and postpubertal time points. Together, these findings suggest that (1) increased commitment of AT-MSCs to adipocyte lineage and decreased differentiation to adipocytes may underlie the small adipocyte phenotype of prenatal T-treated females and (2) excess T-induced changes in steroidal machinery in the VAT likely participate in the programming/maintenance of this defect. [ABSTRACT FROM AUTHOR]

Pumpkin has been suggested to have an antidiabetic effect, but the bioactives involved and molecular mechanisms mediating its hypoglycaemic activity are not clear. This study characterized some of the hypoglycaemic constituents in the crude extract of the Cucurbita moschata stem and investigated the mechanisms of their action. The C. moschata stem extract showed a hypoglycaemic effect in vivo in streptozotocin-induced diabetic mice. Several hypoglycaemic fractions of the extract were identified via cell-based screening, and two of them were confirmed to have hypoglycaemic activities in vivo. Ten compounds were afforded from the 2 fractions. Compounds 9 [(22E,24R)-24-methyl-6β-methoxy-5α-cholesta-7,22-diene-3β,5-diol] and 10 [3β-hydroxy-(22E,24R)-ergosta-5,8,22-trien-7-one] showed an insulin-like activity in normal cells that may be mediated by AMP-activated protein kinase. Compounds 4 (ferulic acid), 8 (syringaresinol) and 9 exhibited an insulin sensitizing and/or insulin substitution function in insulin-resistant cells. Thus, the C. moschata stem contains compounds with potential for managing type 1 or type 2 diabetes.

This systematic review investigated whether the insulin sensitiser metformin has a geroprotective effect in humans. Pubmed and Embase were searched along with databases of unpublished studies. Eligible research investigated the effect of metformin on all-cause mortality or diseases of ageing relative to non-diabetic populations or diabetics receiving other therapies with adjustment for disease control achieved. Overall, 260 full-texts were reviewed and 53 met the inclusion criteria. Diabetics taking metformin had significantly lower all-cause mortality than non-diabetics (hazard ratio (HR) = 0.93, 95%CI 0.88–0.99), as did diabetics taking metformin compared to diabetics receiving non-metformin therapies (HR = 0.72, 95%CI 0.65–0.80), insulin (HR = 0.68, 95%CI 0.63–0.75) or sulphonylurea (HR = 0.80, 95%CI 0.66–0.97). Metformin users also had reduced cancer compared to non-diabetics (rate ratio = 0.94, 95%CI 0.92–0.97) and cardiovascular disease (CVD) compared to diabetics receiving non-metformin therapies (HR = 0.76, 95%CI 0.66–0.87) or insulin (HR = 0.78, 95%CI 0.73–0.83). Differences in baseline characteristics were observed which had the potential to bias findings, although statistical adjustments were made. The apparent reductions in all-cause mortality and diseases of ageing associated with metformin use suggest that metformin could be extending life and healthspans by acting as a geroprotective agent. [ABSTRACT FROM AUTHOR]

Baicalein, a major component in Scutellaria baicalensis and Oroxylum indicum , is used as dietary supplement in Asia. In this study, we characterized the insulin-sensitizing activity of baicalein and found that baicalein improved insulin resistance by reducing the expression of SOCS3, increasing the phosphorylation of IRS1 and Akt1, reducing the phosphorylation of GSK3β and increasing hepatic glycogen level. We further evaluated the preventive effect of baicalein combined with acarbose in mice, aiming to enhance the therapeutic effect and reduce the side-effects of acarbose. The combination reduced the relative risk of progression from prediabetes to diabetes by 83.3% and the dose of acarbose by 80%. The underlying mechanisms include reducing postprandial hyperglycemia, improving insulin resistance, improving lipid metabolism, and reducing oxidative stress. Our results suggest that the consumption of 195–780 mg/d baicalein might improve the efficacy of acarbose on diabetes prevention and reduce the side-effects of acarbose in long-term acarbose users. [ABSTRACT FROM AUTHOR]

Metformin, a biguanide derivate, is known as the first-line antidiabetic agent for type 2 diabetes mellitus (T2DM) treatment. It reduces insulin resistance and decreases blood glucose concentration by inhibiting gluconeogenesis and suppressing hepatic glucose production with improved peripheral tissue insulin sensitivity. As an insulin sensitizer, metformin takes pleiotropic actions and exerts protective effects on multiple organs mainly in insulin-targeted tissues such as liver, muscle, and adipose tissues. Recent studies discover that metformin also plays essential roles in heart and pancreatic β cells — two important organs in metabolic regulation. Metformin not only protects T2DM patients from cardiovascular diseases and heart failure, but also restores insulin secretion activities and protects pancreatic β cells from lipotoxicity or glucotoxicity. Although accumulated evidence shed light on the metformin action, the precise mechanism of metformin is still under investigation. Further laboratory investigations and clinical trials are needed to pinpoint a map of metformin action. Based on recent findings, this review characterizes the beneficial role of metformin in cardiovascular diseases and pancreatic β cells. [ABSTRACT FROM AUTHOR]

Objectıve: The aim of the study is to investigate the effect of myo-inositol (MYO) on pregnancy rates of patients diagnosed with polycystic ovary syndrome (PCOS) who undergone controlled ovulation induction and intrauterine insemination (IUI). Methods: A total of 196 infertile patients diagnosed with PCOS and admitted to Dokuz Eylul University Faculty of Medicine were included in the study between March 2013 and May 2016. The patients in group 1 (n = 98) were given 4 g MYO and 400 μg folic acid before and during ovulation induction. The patients undergone controlled ovarian hyperstimulation (COH) with recombinant FSH and IUI. The patients in group 2 (n = 98), were given recombinant FSH directly and 400 μg folic acid. The primary outcome measure of this study was the clinical pregnancy rate. Results: In group 1, 9 patients conceived spontaneous pregnancy. During COH + IUI treatment three cycles were canceled in group 1 and 8 cycles in group 2. Total rFSH dose and cycle duration were significantly lower and clinical pregnancy rates were higher in group 1. The pregnancy rate for group 1 was %18.6 and for group 2 was %12.2. Conclusıons: This study shows that MYO should be considered in the treatment of infertile PCOS patients. MYO administration increases clinical pregnancy rates, lowers total rFSH dose and the duration of the ovulation induction. [ABSTRACT FROM AUTHOR]

Objective: The concurrent use of an insulin sensitizer in type 2 diabetes mellitus (T2DM) patients with inadequate glycemic control on basal-bolus insulin may help improve glycemic control while limiting further insulin requirement. Bromocriptine-QR (B-QR), a quick release, sympatholytic, dopamine D2 receptor agonist therapy for T2DM, is a postprandial insulin sensitizer. This study evaluated the effect of B-QR on dysglycemia in T2DM subjects with suboptimal glycemic control on basal-bolus insulin plus metformin.Methods: The effect of once-daily morning administration of B-QR on dysglycemia was evaluated in 60 T2DM subjects derived from the Cycloset Safety Trial, with HbA1c >7% on basal-bolus insulin plus metformin at baseline, randomized to B-QR (N = 44) versus placebo (N = 16) and completed 12 weeks of study drug treatment. The analyses also included a subset of subjects on high-dose insulin (total daily insulin dose (TDID) ≥70 units; N = 36: 27 B-QR; 9 placebo).Results: Subjects were well matched at baseline. After 12 weeks of B-QR treatment, mean % HbA1c decreased by -0.73% relative to baseline (p < 0.001) and by -1.13 relative to placebo (p < 0.001). In the high-dose insulin subset, B-QR therapy resulted in % HbA1c reductions of -0.95 and -1.49 relative to baseline (p < 0.001) and placebo (p = 0.001) respectively. Secondary analyses of treatment effect at 24 and 52 weeks demonstrated similar influences of B-QR on HbA1c. The fasting plasma glucose (FPG) and TDID changes within each treatment group were not significant. More subjects achieved HbA1c ≤7 at 12 weeks with B-QR relative to placebo (36.4% B-QR vs 0% placebo, Fisher's exact 2-sided p = 0.003 in the entire cohort and 37% vs 0%, 2-sided p = 0.039 in the high-dose insulin subset).Conclusion: B-QR therapy improves glycemic control in T2DM subjects whose glycemia is poorly controlled on metformin plus basal-bolus insulin, including individuals on high-dose basal-bolus insulin. This glycemic impact occurred without significant change in FPG, suggesting a postprandial glucose lowering mechanism of action. Cycloset Safety Trial registration: ClinicalTrials.gov Identifier: NCT00377676. [ABSTRACT FROM AUTHOR]

Insulin resistance (IR) plays a pivotal role in PCOS. Insulin-sensitizer agents such as metformin and inositols have been shown to improve the endocrine and metabolic aspects of PCOS. The purpose of this study is to compare their effects on the clinical and metabolic features of the women with PCOS. Fifty PCOS women with IR and/or hyperinsulinemia were randomized to treatment with metformin (1500 mg/day) or myo-inositol (4 g/day). IR was defined as HOMA-IR >2.5, while hyperinsulinemia was defined as a value of AUC for insulin after a glucose load over the cutoff of our laboratory obtained in normal women. The Matsusa Index has been calculated. The women have been evaluated for insulin secretion, BMI, menstrual cycle length, acne and hirsutism, at baseline and after 6 months of therapy. The results obtained in both groups were similar. The insulin sensitivity improved in both treatment groups. The BMI significantly decreased and the menstrual cycle was normalized in about 50% of the women. No significant changes in acne and hirsutism were observed. The two insulin-sensitizers, metformin and myo-inositol, show to be useful in PCOS women in lowering BMI and ameliorating insulin sensitivity, and improving menstrual cycle without significant differences between the two treatments. [ABSTRACT FROM AUTHOR]

Introduction: 'Insulin sensitizers' derived discoveries of the Takeda Company in 1970s. Pioglitazone remains the best in class with beneficial pleiotropic pharmacology, although use is limited by tolerability issues. Various attempts to expand out of this class assumed the primary molecular target was the transcription factor, PPARγ. Findings over the last 10 years have identified new targets of thiazolidinediones (TZDs) that should alter the drug discovery paradigm., Areas Covered: We review structural classes of experimental insulin sensitizer drugs, some of which have attained limited approval in some markets. The TZD pioglitazone, originally approved in 1999 as a secondary treatment for type 2 diabetes, has demonstrated benefit in apparently diverse spectrums of disease from cardiovascular to neurological issues. New TZDs modulate a newly identified mitochondrial target (the mitochondrial pyruvate carrier) to reprogram metabolism and produce insulin sensitizing pharmacology devoid of tolerability issues., Expert Opinion: Greater understanding of the mechanism of action of insulin sensitizing drugs can expand the rationale for the fields of treatment and potential for treatment combinations. This understanding can facilitate the registration and broader use of agents with that impact the pathophysiology that underlies chronic metabolic diseases as well as host responses to environmental insults including pathogens, insulin sensitizer, MPC, mitochondrial target, metabolic reprogramming, chronic and infectious disease.

Insulin resistance is a major risk factor for type 2 diabetes. AMP-activated protein kinase (AMPK) is a drug target in the improvement of insulin sensitivity. Several insulin-sensitizing medicines are able to activate AMPK through inhibition of mitochondrial functions. These drugs, such as metformin and STZ, inhibit ATP synthesis in mitochondria to raise AMP/ATP ratio in the process of AMPK activation. However, chemicals that activate AMPK directly or by activating its upstream kinases have not been approved for treatment of type 2 diabetes in humans. In an early study, we reported that berberine inhibited oxygen consumption in mitochondria, and increased AMP/ATP ratio in cells. The observation suggests an indirect mechanism for AMPK activation by berberine. Berberine stimulates glycolysis for ATP production that offsets the cell toxicity after mitochondria inhibition. The study suggests that mitochondrial inhibition is an approach for AMPK activation. In this review article, literature is critically reviewed to interpret the role of mitochondria function in the mechanism of insulin resistance, which supports that mitochondria inhibitors represent a new class of AMPK activator. The inhibitors are promising candidates for insulin sensitizers. This review provides a guideline in search for small molecule AMPK activators in the drug discovery for type 2 diabetes.

Thiazolidinedione (TZD) is a powerful insulin sensitizer in the treatment of type 2 diabetes. It acts as a ligand to the nuclear receptor PPARγ (peroxisome proliferator-activated receptor-gamma) and induces transcription of PPARγ-responsive genes. TZD controls lipid synthesis and storage in adipose tissue, liver and many other tissues through PPARγ. Derivatives of TZD, such as rosiglitazone (Avandia) and pioglitazone (Actos), are more powerful than metformin or berberine in insulin sensitization. Although they have common side effects such as weight gain and edema, these did not influence their clinical application in general. However, recent findings of risk for congestive heart failure and bladder cancer have significantly impaired their future in many countries. European countries have prohibited those drugs, and US will terminate application of rosiglitazone in clinics and hospitals. The multiple country actions may mark the end of TZD era. As a result, there is a strong demand for identification of TZD substitute in the treatment of type 2 diabetes. In this regard, literature about PPARγ ligands and potential TZD substitute are reviewed in this article. Histone deacetylase (HDAC) inhibitor is emphasized as a new class of insulin sensitizer here. Regulators of SIRT1, CREB, NO, p38, ERK and Cdk5 are discussed in the activation of PPARγ.

A novel series of thiazolidine-2,4-diones was designed, synthesized and investigated for anti-diabetic activity. The (2,4-dioxo-1,3-thiazolidin-5-yl)methylphenylbenzamide derivatives contain an amide linkage between the central aryl ring and the hydrophobic tail. Structures of the compounds were confirmed by spectroscopic techniques fourier transform infrared spectroscopy, H-nuclear magnetic resonance and elemental (C, H, N) analysis. The synthesized compounds were evaluated for their in-vivo pharmacological activity (blood glucose and triglyceride lowering activity), where compounds thiazolidinediones-C and thiazolidinediones-E showed significant effects, comparable to the standard pioglitazone. Computational studies positively substantiated the nature and interaction of the designed compounds with peroxisome proliferator-activated receptor gamma. [ABSTRACT FROM AUTHOR]

Background: Abundant evidence from epidemiological and clinical studies has proven that diabetes mellitus (DM) is correlated with an increased incidence of dementia and Alzheimer's disease (AD). Insulin resistance is considered to play an important role in the associations between DM and dementia. However, whether insulin sensitizer drugs are effective in preventing dementia still remains unclear. Methods: Electronic searches of PubMed, EMBASE, Google Scholar, and the ISI Web of Science were conducted to identify studies that reported about the associations between insulin sensitizers and the incidence of dementia. The included studies were reviewed, and a meta-analysis was performed using STATA to determine the combined relative risk(RR) forthe incidence of dementia when using insulin sensitizers. Subgroup analysis and meta regression were also conducted. Results: In total, nine comparisons out of six studies were qualified for inclusion, and data from 544,093 participants were evaluated. The results of the meta-analysis revealed a combined RRof 0.78 (95% CI 0.64-0.95, p = 0.015) for the incidence of dementia when using insulin sensitizers. The incidence rate of dementia was reduced with either metformin (RR 0.79, 95% CI 0.62-1.01, p = 0.064) or thiazolidinediones (RR 0.75, 95% CI 0.56-1.00, p = 0.050), both with a marginal trend toward significance. Conclusions: The results indicate that insulin sensitizer drugs might provide protection against incident dementia. Controlled studies with large samples should be conducted to further confirm these conclusions and provide information for clinical strategies. [ABSTRACT FROM AUTHOR]

Background: Approximately 180 million people worldwide, (3 % of the world's population) are infected with hepatitis C (HCV). Insulin resistance (IR) and type 2 diabetes (T2DM) are common extrahepatic manifestations of chronic HCV infection and associated with poor treatment and liver-related outcomes. The presence of these metabolic complications have been associated with poor response to interferon-based HCV antiviral therapy and increased risk of liver-related outcomes. Metformin, an insulin sensitizer is known to improve HCV treatment response and has been associated with a reduced risk of developing hepatocellular carcinoma (HCC). This study will evaluate the effect of metformin on preventing progression or promoting regression of liver fibrosis, rate of virologic cure (SVR) and other metabolic measures in HCV-HIV co-infected and HCV mono-infected study participants who have IR and are planning on initiating HCV treatment.Methods: This study is a prospective 48-week single-centre, randomized, open-label, controlled trial of HIV-HCV co-infected and HCV mono-infected patients with IR (HOMA-IR ≥ 2.0) who are planning to initiate HCV antiviral therapy. Sixty participants will be recruited from The Ottawa Hospital Viral Hepatitis Clinic. Participants will be randomized in a 1:1 ratio to either arm 1, metformin 2 g (1 g twice daily) plus lifestyle, or to arm 2, lifestyle alone. The primary outcome will be the change in FibroScan® score (kPa) from baseline to week 12 (start of HCV treatment), the end of HCV treatment (week 24) and 24 weeks post HCV treatment (week 48). Secondary outcomes include changes in liver fibrosis using AST to platelet ratio index, changes in glucose and lipid levels, anthropometric measures, changes in alpha-fetoprotein levels, patient acceptability, and changes in dietary and physical activity parameters.Discussion: This pilot study will be the first to evaluate the role of metformin on liver fibrosis in HCV-HIV co-infected and HCV mono-infected patients with IR receiving DAA HCV treatment. If metformin is effective in reducing liver fibrosis in this patient population, this will represent a well-tolerated, easy-to-administer, inexpensive therapy that will protect against negative HCV outcomes. This study will also be an opportunity to evaluate the impact of insulin resistance and hyperglycemia on viral clearance in HCV-infected patients treated with interferon-free regimens.Trial Registration: ClinicalTrials.gov NCT02306070 version 4.0 (June 29, 2015). [ABSTRACT FROM AUTHOR]

Background: Prenatal testosterone (T) excess from days 30-90 of gestation disrupts gonadotropin surge and ovarian follicular dynamics and induces insulin resistance and functional hyperandrogenism in sheep. T treatment from days 60-90 of gestation produces a milder phenotype, albeit with reduced fecundity. Using this milder phenotype, the aim of this study was to understand the relative postnatal contributions of androgen and insulin in mediating the prenatal T induced disruptions in ovarian follicular dynamics. Methods: Four experimental groups were generated: 1) control (vehicle treatment), 2) prenatal T-treated (100 mg i. m. administration of T propionate twice weekly from days 60-90 of gestation), 3) prenatal T plus postnatal anti-androgen treated (daily oral dose of 15 mg/kg/day of flutamide beginning at 8 weeks of age) and 4) prenatal T and postnatal insulin sensitizer-treated (daily oral dose of 8 mg/day rosiglitazone beginning at 8 weeks of age). Follicular response to a controlled ovarian stimulation protocol was tested during their third breeding season. Main outcome measures included the determination of number and size of ovarian follicles and intrafollicular concentrations of steroids. Results: At the end of the controlled ovarian stimulation, the number of follicles approaching ovulatory size (≥6 mm) were ~35 % lower in prenatal T-treated (6.5 ± 1.8) compared to controls (9.8 ± 2.0). Postnatal anti-androgen (10.3 ± 1.9), but not insulin sensitizer (5.0 ± 0.9), treatment prevented this decrease. Preovulatory sized follicles in the T group had lower intrafollicular T, androstenedione, and progesterone compared to that of the control group. Intrafollicular steroid disruption was partially reversed solely by postnatal insulin sensitizer treatment. Conclusions: These results demonstrate that the final preovulatory follicular growth and intrafollicular steroid milieu is impaired in prenatal T-treated females. The findings are consistent with the lower fertility rate reported earlier in these females. The finding that final follicle growth was fully rescued by postnatal anti-androgen treatment and intrafollicular steroid milieu partially by insulin sensitizer treatment suggest that both androgenic and insulin pathway disruptions contribute to the compromised follicular phenotype of prenatal T-treated females. [ABSTRACT FROM AUTHOR]

The incidence of metabolic syndrome (MetS), type II diabetes (T2D) and polycystic ovarian syndrome (PCOS) has been progressively increasing. Insulin resistance (InsR) seems to play a key role in a majority of phenotypes of these conditions, altering metabolic homeostasis, within muscle, liver, adipose and other tissues. Hyperinsulinemia is often associated with InsR and causes hormonal imbalances especially within ovaries and adrenals. Inositol is a polyalcohol, naturally occurring as nine stereoisomers, including D-chiro-inositol (DCI) and myo-inositol (MI), which have prominent roles in the metabolism of glucose and free fatty acids. MI and DCI have been classified as insulin-sensitizers and seem to adequately counteract several InsR-related metabolic alterations with a safe nutraceutical profile. Based on our analysis of selected studies that investigated MI and/or DCI, we conclude that supplementation with MI and/or DCI complement each other in their metabolic actions and act in synergy with other insulin sensitizing drugs and/or nutraceuticals. Nevertheless, considering the possible severe bias due to different methodologies across published studies, we conclude that there is a need for further studies on larger cohorts and with greater statistical power. These should further clarify outcomes and suitable therapeutic dosages of MI and DCI, possibly based on each patient's clinical status. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to compare the effect of Diane-35 versus Diane-35 + metformin on metabolic parameters in Chinese PCOS patients. Methods: Patients getting individualized life-style modification were treated with Diane-35. Metformin was added according to its indication. Within a 3-month prospective study, metabolic parameters were assessed. Results: Eighty-three patients were recruited, 45 using Diane-35 and 38 Diane-35 plus metformin. Using Diane-35, triglycerides (TG) (p < 0.05) and tendencially (p < 0.1) total cholesterol (TC) increased, but significant positive effects on BMI, high-density lipoprotein cholesterol (HDL-C), and HDL-C/TC ratio were observed. Other lipids and the parameters for glucose metabolism remained unchanged. In the combination group, no negative effect on TG and TC was seen, other lipid fractions improved, as well as BMI, % body fat, and all parameters for glucose metabolism like fasting plasma glucose (FPG), fasting insulin, HOMA-insulin-resistance index, and insulin sensitivity index (ISI), whereby the beneficial effect of metformin got significance compared with Diane-35 for BMI, FPG, and ISI. Conclusion: With the exception of increasing triglycerides, Diane-35 had no relevant negative effects in the metabolic system. It does not negatively impact the beneficial effects of metformin in lipids and glucose metabolism. Diane-35 plus metformin is effective in improving the metabolic profile of Chinese PCOS patients. [ABSTRACT FROM AUTHOR]

Saroglitazar is a novel nonthiazolidinediones (TZD) and nonfibric acid derivative designed to act as dual regulator of lipids and glucose metabolism by activating peroxisome proliferator-activated receptors (PPAR). These studies evaluate the efficacy and safety profile of Saroglitazar in preclinical in vitro and in vivo models. The EC50 values of Saroglitazar assessed in HepG2 cells using PPAR transactivation assay for hPPARα and hPPARγ were 0.65 pmol/L and 3 nmol/L, respectively. In db/db mice, 12-day treatment with Saroglitazar (0.01-3 mg/kg per day, orally) caused dose-dependent reductions in serum triglycerides (TG), free fatty acids (FFA), and glucose. The ED50 for these effects was found to be 0.05, 0.19, and 0.19 mg/kg, respectively with highly significant (91%) reduction in serum insulin and AUC-glucose following oral glucose administration (59%) at 1 mg/kg dose. Significant reduction in serum TG (upto 90%) was also observed in Zucker fa/fa rats, Swiss albino mice, and in high fat -high cholesterol (HF-HC)-fed Golden Syrian hamsters. LDL cholesterol was significantly lowered in hApoB100/hCETP double transgenic mice and HF-HC diet fed Golden Syrian Hamsters. Hyperinsulinemic-Euglycemic clamp study in Zucker fa/fa rats demonstrated potent insulin-sensitizing activity. Saroglitazar also showed a significant decrease in SBP (22 mmHg) and increase (62.1%) in serum adiponectin levels in Zucker fa/fa rats. A 90-day repeated dose comparative study in Wistar rats and marmosets confirmed efficacy (TG lowering) potential of Saroglitazar and has indicated low risk of PPAR-associated side effects in humans. Based on efficacy and safety profile, Saroglitazar appears to have good potential as novel therapeutic agent for treatment of dyslipidemia and diabetes. [ABSTRACT FROM AUTHOR]

Pumpkin has been suggested to have an antidiabetic effect, but the bioactives involved and molecular mechanisms mediating its hypoglycaemic activity are not clear. This study characterized some of the hypoglycaemic constituents in the crude extract of the Cucurbita moschata stem and investigated the mechanisms of their action. The C. moschata stem extract showed a hypoglycaemic effect in vivo in streptozotocin-induced diabetic mice. Several hypoglycaemic fractions of the extract were identified via cell-based screening, and two of them were confirmed to have hypoglycaemic activities in vivo . Ten compounds were afforded from the 2 fractions. Compounds 9 [(22 E ,24 R )-24-methyl-6 β -methoxy-5 α -cholesta-7,22-diene-3 β ,5-diol] and 10 [3 β -hydroxy-(22 E ,24 R )-ergosta-5,8,22-trien-7-one] showed an insulin-like activity in normal cells that may be mediated by AMP-activated protein kinase. Compounds 4 (ferulic acid), 8 (syringaresinol) and 9 exhibited an insulin sensitizing and/or insulin substitution function in insulin-resistant cells. Thus, the C. moschata stem contains compounds with potential for managing type 1 or type 2 diabetes. [ABSTRACT FROM AUTHOR]

Non-alcoholic fatty liver disease (NAFLD), including the disease stages steatosis and non-alcoholic steatohepatitis, is the most common cause of chronic liver disease worldwide and linked to the epidemic of diabetes mellitus and obesity. It is characterized by a high cardiovascular and liver-related mortality and expected to be the leading cause for liver transplantation in the near future. This review summarizes recent progress made in our understanding of the disease pathogenesis and the clinical management of patients with NAFLD. Strategies to manage diabetes mellitus will be evaluated in terms of their effectiveness in treating patients with NAFLD and novel pharmacological targets capable to treat diabetes mellitus and NAFLD will be highlighted. [ABSTRACT FROM AUTHOR]