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Transforming growth factor β1 (TGF-β1) regulates a wide variety of events in adult bone marrow (BM), including quiescence of hematopoietic stem cells, via undefined mechanisms. Because megakaryocytes (MKs)/platelets are a rich source of TGF-β1, we assessed whether TGF-β1 might inhibit its own production by comparing mice with conditional inactivation of Tgfb1 in MKs (PF4Cre;Tgfb1flox/flox) and control mice. PF4Cre;Tgfb1flox/flox mice had ∼30% more MKs in BM and ∼15% more circulating platelets than control mice (P < .001). Thrombopoietin (TPO) levels in plasma and TPO expression in liver were approximately twofold higher in PF4Cre;Tgfb1flox/flox than in control mice (P < .01), whereas TPO expression in BM cells was similar between these mice. In BM cell culture, TPO treatment increased the number of MKs from wild-type mice by approximately threefold, which increased approximately twofold further in the presence of a TGF-β1–neutralizing antibody and increased the number of MKs from PF4Cre;Tgfb1flox/flox mice approximately fourfold. Our data reveal a new role for TGF-β1 produced by MKs/platelets in regulating its own production in BM via increased TPO production in the liver. Additional studies are required to determine the mechanism.

Vaso-occlusive episode (VOE) is a common and critical complication of sickle cell disease (SCD). Its pathogenesis is incompletely understood. von Willebrand factor (VWF), a multimeric plasma hemostatic protein synthesized and secreted by endothelial cells and platelets, is increased during a VOE. However, whether and how VWF contributes to the pathogenesis of VOE is not fully understood. In this study, we found increased VWF levels during tumor necrosis factor (TNF)–induced VOE in a humanized mouse model of SCD. Deletion of endothelial VWF decreased hemolysis, vascular occlusion, and organ damage caused by TNF-induced VOE in SCD mice. Moreover, administering ADAMTS13, the VWF-cleaving plasma protease, reduced plasma VWF levels, decreased inflammation and vaso-occlusion, and alleviated organ damage during VOE. These data suggest that promoting VWF cleavage via ADAMTS13 may be an effective treatment for reducing hemolysis, inflammation, and vaso-occlusion during VOE.

This study was aimed to determine and compare the effect of different percentages of extraction solvent ethanol 0% (E0), 20% (E20), and 40% (E40) with water (vol/vol) as well as extraction time 6, 9 and 15 h on the yield and antioxidant potential of Pinus densiflora needle (PDN) and bark (PDB) extracts. Extraction was performed at 60 ± 5 °C. A maximum yield of 10.99 ± 0.96 and 16.86 ± 1.96% from 20 g of PDN and PDB was obtained with E40 at 15 h of extraction, respectively. Extraction of PDN and PDB using E20 or E40 for 6–15 h significantly (P

Although current chemotherapeutic agents are active at the beginning of therapy, the most common risk is the development of resistance during later stages in almost all cancer types including breast cancer. Hence, investigation of novel drugs is still a priority goal for cancer treatment. The objective of the present study is to investigate the anticancer effect of a derivative of stilbene, deoxyrhapontigenin (DR) isolated from Rheum undulatum L. root extracts against the chemoresistant MCF-7/adr and its parental MCF-7 human breast cancer cells. The morphological images indicate that DR induces an extensive cytoplasmic vacuolation in breast cancer cells. Mechanistic investigations revealed that DR treatment causes endoplasmic reticulum (ER) dilation and upregulated the expression of ER stress markers GRP78, IRE1α, eIF2α, CHOP, JNK, and p38. Subsequently, we also identified that DR increases the levels of apoptotic fragment of PARP (89 kDa) in breast cancer cells. Blocking the expression of one of the components of the ER stress–mediated apoptosis pathway, CHOP using siRNA significantly decreased DR-induced apoptotic cleavage of PARP. In summary, the present study suggests that the induction of ER stress–mediated apoptosis by DR may account for its cytotoxic effects in human breast cancer cells.

In the present study, we investigated the anticancer activity of Pinus radiata bark extract (PRE) against MCF-7 human breast cancer cells. First, we observed that PRE induces potent cytotoxic effects in MCF-7 cells. The cell death had features of cytoplasmic vacuolation, plasma membrane permeabilization, chromatin condensation, phosphatidylserine externalization, absence of executioner caspase activation, insensitivity to z-VAD-fmk (caspase inhibitor), increased accumulation of autophagic markers, and lysosomal membrane permeabilization (LMP). Both the inhibition of early stage autophagy flux and lysosomal cathepsins did not improve cell viability. The antioxidant, n-acetylcysteine, and the iron chelator, deferoxamine, failed to restore the lysosomal integrity indicating that PRE-induced LMP is independent of oxidative stress. This was corroborated with the absence of enhanced ROS production in PRE-treated cells. Chelation of both intracellular calcium and zinc promotes PRE-induced LMP. Geranylgeranylacetone, an inducer of Hsp70 expression, also had no significant protective effect on PRE-induced LMP. Moreover, we found that PRE induces endoplasmic reticulum (ER) stress and mitochondrial membrane depolarization in MCF-7 cells. The ER stress inhibitor, 4-PBA, did not restore the mitochondrial membrane integrity, whereas cathepsin inhibitors demonstrated significant protective effects. Collectively, our results suggest that PRE induces an autophagic block, LMP, ER stress, and mitochondrial dysfunction in MCF-7 cells. However, further studies are clearly warranted to explore the exact mechanism behind the anticancer activity of PRE in MCF-7 human breast cancer cells.

It is well established that various extraction factors, including the method, temperature, time, and solvent system, significantly influence the antioxidant quality of plant-derived products. Previously, we observed that extraction of Pinus densiflora bark (PDB) by the most common traditional Soxhlet method using water at two different temperature conditions 60°C and 100°C for 6-15 h noticeably altered their antioxidant quality. In this study, we examined the impact of different extraction solvents such as ethanol, methanol, isopropanol, acetonitrile, and acetone at a different percentage with water (vol/vol) on antioxidant efficiency as well as the total phenolic content (TPC) of PDB extracts. Among the fourteen different PDB extracts, the extracts obtained from 20% ethanol (E20), 40% ethanol (E40), and 20% acetonitrile (ACN20) showed more significant antioxidant potential, as well as high total phenol content (TPC). Extracts from other aqueous mixtures of organic solvents such as isopropanol, acetone, and methanol, as well as water, showed lesser antioxidant capacity and also had less TPC compared to these three most active extracts, E20, E40, and ACN20. Moreover, using ethanol at 100% for extraction significantly decreased the TPC and antioxidant capacity of PDB extracts. Data are implicating that an increased phenolic content in PDB extracts proportionally increases their antioxidant efficiency.

Background Regulation of a persistently-activated inflammatory response in macrophages is an important target for treatment of various chronic diseases. Pine needle extracts are well known to have potent immunomodulatory effects. The current study was designed to evaluate the effects of Pinus densiflora needle supercritical fluid extract (PDN-SCFE) on bacterial lipopolysaccharide (LPS)-induced inflammatory response in RAW 264.7 murine macrophages. Methods Cytotoxic effect of PDN-SCFE was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The levels of nitric oxide (NO) and the corresponding enzyme, inducible nitric oxide synthase (iNOS), were quantified by Griess and immunoblotting methods, respectively. The levels of cytokines were quantified using commercial ELISA kits. Quantitative real-time PCR (qRT-PCR) analysis was performed to assess the mRNA expression of iNOS and cytokines. To elucidate the mechanism of action, the involvement of nuclear transcription factor-kappa B (NFκB), mitogen activated protein kinases (MAPKs) and Janus kinase-signal transducers and activators of transcription (JAK-STAT) pathways were examined by an immunoblotting method. In addition, the cellular localization of NFκB was analyzed by immunofluorescence staining. Results MTT assay results indicated that PDN-SCFE is non-toxic to RAW 264.7 cells up to a maximum assayed concentration of 40 μg/mL. The PDN-SCFE exhibited a concentration-dependent inhibitory effect on LPS-induced NO production by down regulating the expression of iNOS. In addition, the extract suppressed the LPS-induced expression of interleukin-6 (IL-6) and interleukin-1β (IL-1β) but not tumour necrosis factor-α (TNFα). Mechanistic studies revealed that PDN-SCFE does not influence the NFκB and MAPK pathways. However, it showed a significant inhibitory effect on LPS-induced activation of STAT1 and STAT3 proteins in macrophages. Conclusion The present findings revealed that the anti-inflammatory activity of PDN-SCFE in LPS-challenged RAW 264.7 macrophages is probably caused by the suppression of the JAK-STAT signaling pathway. Graphical Abstract

Falcarindiol (FAD) is a natural polyacetylene compound found rich in many plants of the Umbelliferae family. Previously, we isolated FAD from the rhizome of Cnidium officinale Makino, which belongs to the Umbelliferae family and found it to have a significant inhibitory effect on lipopolysaccharide (LPS)-induced production of nitric oxide, a pro-inflammatory molecule in murine macrophage RAW 264.7 cells. In this study, we investigated its effect on the expression of other major pro-inflammatory molecules as well as the mechanism underlying these effects. Pre-treatment of RAW 264.7 cells with FAD suppressed LPS-stimulated mRNA expression of inducible nitric oxide synthase (iNOS), tumor necrosis factor alpha (TNFα), interleukin-6 (IL-6), and interleukin-1 beta (IL-1β) and thereby reduced the respective protein levels. Mechanistic studies demonstrated that FAD attenuated the LPS-induced activation of JNK, ERK, STAT1, and STAT3 signaling molecules. Moreover, we found that FAD did not influence LPS-induced activation of p38 and NFκB signaling pathways. Collectively, this study provides evidence that FAD inhibits the production of major pro-inflammatory molecules in LPS-challenged murine macrophages via suppression of JNK, ERK, and STAT signaling pathways.

Background: Most of the currently available oral hypoglycemic drugs for the treatment of diabetes mellitus elicit detrimental side effects. Hence, the search for plant-derived products for the treatment of diabetes continues. Gossypin, a pentahydroxy flavone glucoside found in the flowers of Hibiscus vitifolius, has many biological properties, including as an antioxidant, anti-inflammatory and anticancer agent. The aim of the present study was to evaluate the effect of gossypin in streptozotocin (STZ)-induced experimental diabetes in rats. Methods: Diabetic rats were administered 20 mg/kg per day gossypin orally for 30 days. On the 28th day, rats were subjected to an oral glucose tolerance test. In addition, blood glucose, plasma insulin, hemoglobin, and HbA1c levels were determined, as was the glycogen content of the liver and muscles. Plasma protein and blood urea were also estimated. Results: Oral administration of gossypin to diabetic rats resulted in improved glucose tolerance. Increased blood glucose and HbA1c levels and the reduced plasma insulin and hemoglobin levels in diabetic rats were significantly reversed to near normal after oral administration of gossypin. Furthermore, the glycogen content of the liver and muscles was significantly improved after gossypin treatment of diabetic rats, and plasma protein and blood urea levels were almost normalized. The data obtained in gossypin-treated rats were comparable with those obtained following gliclazide treatment of rats, a standard reference drug for diabetes. Conclusions: The results of the present study indicate that gossypin has potent antidiabetic activity in STZ-induced experimental diabetes in rats.

Most of the currently available oral hypoglycemic drugs for the treatment of diabetes mellitus elicit detrimental side effects. Hence, the search for plant-derived products for the treatment of diabetes continues. Gossypin, a pentahydroxy flavone glucoside found in the flowers of Hibiscus vitifolius, has many biological properties, including as an antioxidant, anti-inflammatory and anticancer agent. The aim of the present study was to evaluate the effect of gossypin in streptozotocin (STZ)-induced experimental diabetes in rats.Diabetic rats were administered 20 mg/kg per day gossypin orally for 30 days. On the 28th day, rats were subjected to an oral glucose tolerance test. In addition, blood glucose, plasma insulin, hemoglobin, and HbA1c levels were determined, as was the glycogen content of the liver and muscles. Plasma protein and blood urea were also estimated.Oral administration of gossypin to diabetic rats resulted in improved glucose tolerance. Increased blood glucose and HbA1c levels and the reduced plasma insulin and hemoglobin levels in diabetic rats were significantly reversed to near normal after oral administration of gossypin. Furthermore, the glycogen content of the liver and muscles was significantly improved after gossypin treatment of diabetic rats, and plasma protein and blood urea levels were almost normalized. The data obtained in gossypin-treated rats were comparable with those obtained following gliclazide treatment of rats, a standard reference drug for diabetes.The results of the present study indicate that gossypin has potent antidiabetic activity in STZ-induced experimental diabetes in rats.