Design and Development of Novel Glitazones for Activation of PGC-1α Signaling Via PPAR-γ Agonism: A Promising Therapeutic Approach against Parkinson's Disease.

Herein, we rationally designed and developed two novel glitazones (G1 and G2) to target peroxisome proliferator-activated receptor-gamma coactivator 1-alpha (PGC-1α) signaling through peroxisome proliferator-activated receptors (PPAR)-γ agonism as a therapeutic for Parkinson's disease (PD). The synthesized molecules were analyzed by mass spectrometry and NMR spectroscopy. The neuroprotective functionality of the synthesized molecules was assessed by a cell viability assay in lipopolysaccharide-intoxicated SHSY5Y neuroblastoma cell lines. The ability of these new glitazones to scavenge free radicals was further ascertained via a lipid peroxide assay, and pharmacokinetic properties were verified using in silico absorption, distribution, metabolism, excretion, and toxicity analyses. The molecular docking reports recognized the mode of interaction of the glitazones with PPAR-γ. The G1 and G2 exhibited a noticeable neuroprotective effect in lipopolysaccharide-intoxicated SHSY5Y neuroblastoma cells with the half-maximal inhibitory concentration value of 2.247 and 4.509 µM, respectively. Both test compounds prevented 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced motor impairment in mice, as demonstrated by the beam walk test. Further, treating the diseased mice with G1 and G2 resulted in significant restoration of antioxidant enzymes glutathione and superoxide and reduced the intensity of lipid peroxidation inside the brain tissues. Histopathological analysis of the glitazones-treated mice brain revealed a reduced apoptotic region and a rise in the number of viable pyramidal neurons and oligodendrocytes. The study concluded that G1 and G2 showed promising results in treating PD by activating PGC-1α signaling in brain via PPAR-γ agonism. However, more extensive research is necessary for a better understanding of functional targets and signaling pathways.

Anti-Tumor Potential of Gymnema sylvestre Saponin Rich Fraction on In Vitro Breast Cancer Cell Lines and In Vivo Tumor-Bearing Mouse Models.

Gymnema sylvestre (GS) is a perennial woody vine native to tropical Asia, China, the Arabian Peninsula, Africa and Australia. GS has been used as a medicinal plant with potential anti-microbial, anti-inflammatory and anti-oxidant properties. This study was conceptualized to evaluate the cytotoxicity potential of Gymnema sylvestre saponin rich fraction (GSSRF) on breast cancer cell lines (MCF-7 and MDA-MB-468) by SRB assay. The anti-tumor activity of GSSRF was assessed in tumor-bearing Elrich ascites carcinoma (EAC) and Dalton's lymphoma ascites (DLA) mouse models. The anti-oxidant potential of GSSRF was assessed by DPPH radical scavenging assay. The acute toxicity of GSSRF was carried out according to OECD guideline 425. The yield of GSSRF was around 1.4% and the presence of saponin content in GSSRF was confirmed by qualitative and Fourier transform infrared spectroscopic (FTIR) analysis. The in vitro cytotoxic effects of GSSRF on breast cancer cell lines were promising and found to be dose-dependent. An acute toxicity study of GSSRF was found to be safe at 2000 mg/kg body weight. GSSRF treatment has shown a significant increase in the body weight and the life span of EAC-bearing mice in a dose-dependent manner when compared with the control group. In the solid tumor model, the doses of 100 and 200 mg/kg body weight per day have shown about 46.70% and 60.80% reduction in tumor weight and controlled the tumor weight until the 30th day when compared with the control group. The activity of GSSRF in both models was similar to the cisplatin, a standard anticancer agent used in the study. Together, these results open the door for detailed investigations of anti-tumor potentials of GSSRF in specific tumor models, mechanistic studies and clinical trials leading to promising novel therapeutics for cancer therapy.

Manganese chloride (MnCl2) induced novel model of Parkinson's disease in adult Zebrafish; Involvement of oxidative stress, neuroinflammation and apoptosis pathway.

Parkinson's disease (PD) is a progressive neurodegenerative disorder imposing a severe health and socioeconomic burden worldwide. Existing pharmacological approaches for developing PD are poorly developed and do not represent all the characteristics of disease pathology. Developing cost-effective, reliable Zebrafish (ZF) model will meet this gap. The present study was conceived to develop a reliable PD model in the ZF using manganese chloride (MnCl2). Here, we report that chronic exposure to 2 mM MnCl2 for 21 days produced non-motor and motor PD-like symptoms in adult ZF. Compared with control fish, MnCl2-treated fish showed reduced locomotory activity, indicating a deficit in motor function. In the light-dark box test, MnCl2-treated fish exhibited anxiety and depression-like behavior. MnCl2-treated fish exhibited a less olfactory preference for amino acids, indicating olfactory dysfunction. These behavioral symptoms were associated with decreased dopamine and increased DOPAC levels. Furthermore, oxidative stress-mediated apoptotic pathway, decreased brain derived neurotropic factor (BDNF) and increased pro-inflammatory cytokines levels were observed upon chronic exposure to MnCl2 in the brain of ZF. Thus, MnCl2-induced PD in ZF can be a cost-effective PD model in the drug discovery process. Moreover, this model could be potentially utilized to investigate the molecular pathways underlying the multifaceted pathophysiology which leads to PD using relatively inexpensive species. MnCl2 being heavy metal may have other side effects in addition to neurotoxicity. Our model recapitulates most of the hallmarks of PD, but not all pathological processes are involved. Future studies are required to recapitulate the complete pathophysiology of PD.