Assessment of Therapeutic Excellence of Jasminum humile (Linn.) and Pleurospermum candollei (DC.) C.B. Clarke Via in vitro and in vivo Assays

Abstract

Medicinal plants contain several bioactive chemical constituents that provide significant therapeutic effects, either directly or indirectly, proving to be an effective source to deal with the current healthcare challenges including infectious disorders, inflammation, cardiovascular diseases, neurodegenerative diseases, cancer, diabetes and several other types of lethal ailments. On the basis of ethnopharmacological studies, two medicinally potent plants like Jasminum humile and Pleurospermum candollei were selected for this study. J. humile is one of potent therapeutic plants which is traditionally used as a remedy in treating diseases such as ringworm, chronic fistulas, hard lumps, anxiety, inflammatory disorders, and neurological problems. It is also used as an astringent, antiseptic, antispasmodic, and cardiac tonic. While P. candollei is a local vegetable which is traditionally employed to treat various serious diseases including digestive disorders, abdominal distress, respiratory issues, cardiac diseases, pain, diarrhea, and infertility complications. It is also used as a spice to introduce flavor in food. This research was conducted to investigate the pharmacological and therapeutic potential of selected plants through in-vitro antioxidant assays and in-vivo anti-inflammatory and anti-diabetic studies. The present study investigates the pharmacological potentials of J. humile and P. candollei against a few important clinical issues like oxidative stress, hepatotoxicity, and inflammation. Considering the aim of developing natural, plant-based therapeutic modes as effective alternatives for the prevention and treatment of such conditions. Both samples were collected, dried and prepared dried powder was extracted with methanol, ethanol and water by shaking it continuously at room temperature. Prepared extract was dried through vacuum distillation and semi-solid extracts were obtained. Initial qualitative phytochemical studies were performed to assess the presence of various phytochemicals such as terpenoids, phalobatanins, triterpenoids, glycosides, oils, resins, alkaloids, carbohydrates, proteins, flavonoids, steroids, phytosteroids, betacyanin, anthocyanins, saponins, vitamins, sterols, quinones, and phenols. HPLC and FTIR analysis was conducted for further characterization of phytochemical antioxidants in relevant extracts. Based on qualitative and chromatographic analysis, quantitative assays were conducted. In-vitro antioxidant assays (FRAP, TAC. DPPH, hydroxyl ion, and metal Abstract XI chelation) investigated the antioxidant properties of selected plant extracts. However, cytotoxic studies were performed to assess the toxicity of extracts in rats. Hepatoprotective potential of JHM and PCM was evaluated against oxidative damage mediated by carbon tetrachloride (CCl4) in rats. While JHE was examined for therapeutic effects against renal toxicity instigated by CCl4. Rats were divided into groups; CCl4 was injected intraperitoneally, and various plant doses and reference drugs were administered orally. Blood and organs (i.e. liver and kidney) were extracted from various groups for enzymatic, free radicals and serum analysis. TRIzol method was used for RNA extraction and qRTPCR analysis was performed for assessment of various inflammatory, apoptotic, fibrosis and renal markers. Similarly, induction of streptozotocin (STZ) along-with nicotinamide mediated type 2 diabetes in rats and diabetic nephropathy was induced. Blood glucose level was measured along with enzymatic analysis. qRT-PCR analysis was done for investigation of mRNA expression levels of diabetic genetic markers. Flavonoids, tannins, and phenolic contents were quantified in significant quantity in J. humile methanol extract (JHM), P. candollei methanol extract (PCM), and P. candollei ethanol extract (PCE). HPLC analysis confirmed the presence of almost 10 polyphenolics in relevant extracts such as rutin, syringic acid, catechin, and vanillic acid found in JHM, emodin and catechin in PCM, cinnamic acid, rutin, and gallic acid in PCE. These extracts exhibited high antioxidant potential, least IC50 values against free radicals, strong correlations of TPC and TFC with all in vitro antioxidant assays conducted. High antidiabetic activity was found in PCE against α-glucosidase enzyme at higher concentrations. Cytotoxic studies of JHM, PCM, PCE on rats showed that extracts were non-toxic even at higher concentration (2000 and 3000 mg/kg bw) when administered orally. Enzymatic antioxidants and GSH were decreased in CCl4 treated groups while plant extracts normalized the levels of these antioxidants and neutralized the higher production of free radicals due to CCl4 induction. At molecular levels, CCl4 increased the expression of ER stress genes (Xbp1s, Xbp1u, Xbp1t), inflammatory mediators (i.e. IL-6, MCP, TNF-α), apoptotic (Chop, Caspase 3) and fibrosis (Tgf-β, col1a1) markers. JHM and PCM reversed the toxic effects of CCl4 on liver and kidney of rats and normalized the expression levels of these above-mentioned genes. PCE reduced the blood glucose levels and risk of obesity Abstract XII in pre-induced diabetic rats. At molecular level, STZ increased inflammatory, fibrosis and apoptotic markers while PCE decreased the expression of these markers at normal level. Histological studies further confirmed the therapeutic effects of JHM, PCM and PCE on liver and kidney by showing normal physiology of hepatic and renal tissues. The above results demonstrate strong evidence of using J. humile and P. candollei as promising medicinal agent against various diseases with no side effects. However, clinical trials will further elaborate the efficacy and potency of these plants to be introduced as a drug.