piperine and Fibrosis

Myocardial infarction (MI) eventually exacerbates inflammatory response due to the release of inflammatory and pro-inflammatory factors. The aim of this study is to explore the protective efficacy of piperine supplementation against the inflammatory response in isoproterenol (ISO)-induced MI. Masson Trichome staining was executed to determine myocardial tissue architecture. Immunohistochemistry was performed for IL-6, TNF-α. RT-PCR studies were performed to ascertain the gene expression of IL-6, TNF-α, iNOS, eNOS, MMP-2, MMP-9, and collagen-III. Western blotting was performed to determine expression of HIF-1α, VEGF, Nrf-2, NF-ƙB, Cox-2, p-38, phospho-p38, ERK-1/2, phospho-ERK-1/2, and collagen-I. HIF-1α, VEGF, and iNOS expression were significantly upregulated with concomitant decline in eNOS expression in the heart myocardial tissue of rats received ISO alone whereas piperine pretreatment prevented these changes in ISO administered rats. Current results revealed ROS-mediated activation of MAPKs, namely, p-p38, p-ERK1/2 in the heart tissue of ISO administered group. Piperine pretreatment significantly prevented these changes in ISO treated group. NF-κB is involved in the modulation of gene expressions responsible for tissue repair. ISO-induced NF-κB-p65 expression was significantly reduced in the group pretreated with piperine and mitigated extent of myocardial inflammation. A significant increase in cardiac fibrosis upon ISO treatment was reported due to the increased hydroxyproline content, MMP-2 & 9 and upregulation of collagen-I protein compared to control group. All these cardiac hypertrophy markers were decreased in 'piperine pretreated ISO administered group' compared to group received ISO injection. Current findings concluded that piperine as a nutritional intervention could prevent inflammation of myocardium in ISO-induced MI.

Topics: Adrenergic beta-Agonists; Alkaloids; Animals; Benzodioxoles; Cardiomegaly; Cytokines; Endothelium; Fibrosis; Inflammation; Isoproterenol; Male; Myocardial Infarction; Myocardium; Piperidines; Polyunsaturated Alkamides; Rats; Rats, Wistar; Signal Transduction; Transcription Factor RelA

Chronic pancreatitis (CP) is characterized by recurrent pancreatic injury, resulting in inflammation and fibrosis. Currently, there are no drugs for the treatment of pancreatic fibrosis associated with CP. Piperine, a natural alkaloid found in black pepper, has been reported to show anti‑inflammatory, anti‑oxidative, and antitumor activities. Although piperine exhibits numerous properties in regards to the regulation of diverse diseases, the effects of piperine on CP have not been established. To investigate the effects of piperine on CP in vivo, we induced CP in mice through the repetitive administration of cerulein (50 µg/kg) six times at 1‑h intervals, 5 times per week, for a total of 3 weeks. In the pre‑treatment groups, piperine (1, 5, or 10 mg/kg) or corn oil were administrated orally at 1 h before the first cerulein injection, once a day, 5 times a week, for a total of 3 weeks. In the post‑treatment groups, piperine (10 mg/kg) or corn oil was administered orally at 1 or 2 week after the first cerulein injection. Pancreases were collected for histological analysis. In addition, pancreatic stellate cells (PSCs) were isolated to examine the anti‑fibrogenic effects and regulatory mechanisms of piperine. Piperine treatment significantly inhibited histological damage in the pancreas, increased the pancreatic acinar cell survival, reduced collagen deposition and reduced pro‑inflammatory cytokines and chemokines. In addition, piperine treatment reduced the expression of fibrotic mediators, such as α‑smooth muscle actin (α‑SMA), collagen, and fibronectin 1 in the pancreas and PSCs. Moreover, piperine treatment reduced the production of transforming growth factor (TGF)‑β in the pancreas and PSCs. Furthermore, piperine treatment inhibited TGF‑β‑induced pSMAD2/3 activation but not pSMAD1/5 in the PSCs. These findings suggest that piperine treatment ameliorates pancreatic fibrosis by inhibiting TGF‑β/SMAD2/3 signaling during CP.

Topics: Alkaloids; Animals; Anti-Inflammatory Agents; Benzodioxoles; Disease Models, Animal; Female; Fibrosis; Mice; Mice, Inbred C57BL; Pancreas; Pancreatitis, Chronic; Piperidines; Polyunsaturated Alkamides; Signal Transduction; Smad Proteins; Transforming Growth Factor beta

Mitogen-activated protein kinases (MAPKs) and AMP-activated protein kinase α (AMPKα) play critical roles in the process of cardiac hypertrophy. Previous studies have demonstrated that piperine activates AMPKα and reduces the phosphorylation of extracellular signal-regulated kinase (ERK). However, the effect of piperine on cardiac hypertrophy remains completely unknown. Here, we show that piperine-treated mice had similar hypertrophic responses as mice treated with vehicle but exhibited significantly attenuated cardiac fibrosis after pressure overload or isoprenaline (ISO) injection. Piperine inhibited the transformation of cardiac fibroblasts to myofibroblasts induced by transforming growth factor-β (TGF-β) or angiotensin II (Ang II) in vitro. This anti-fibrotic effect was independent of the AMPKα and MAPK pathway. Piperine blocked activation of protein kinase B (AKT) and, downstream, glycogen synthase kinase 3β (GSK3β). The overexpression of constitutively active AKT or the knockdown of GSK3β completely abolished the piperine-mediated protection of cardiac fibroblasts. The cardioprotective effects of piperine were blocked in mice with constitutively active AKT. Pretreatment with GW9662, a specific inhibitor of peroxisome proliferator activated receptor-γ (PPAR-γ), reversed the effect elicited by piperine in vitro. In conclusion, piperine attenuated cardiac fibrosis via the activation of PPAR-γ and the resultant inhibition of AKT/GSK3β.

Topics: Alkaloids; Angiotensin II; Anilides; Animals; Benzodioxoles; Cell Differentiation; Cells, Cultured; Cytochrome P-450 Enzyme Inhibitors; Fibroblasts; Fibrosis; Glycogen Synthase Kinase 3 beta; Heart; Isoproterenol; Male; Mice; Mice, Inbred C57BL; Myocardium; Myofibroblasts; Piperidines; Polyunsaturated Alkamides; PPAR gamma; Proto-Oncogene Proteins c-akt; RNA Interference; RNA, Small Interfering; Signal Transduction; Transforming Growth Factor beta