Herbal medicinal products have been documented as a significant source for discovering new pharmaceutical molecules that have been used to treat serious diseases. Many plant species have been reported to have pharmacological activities attributable to their phytoconstituents such are glycosides, saponins, flavonoids, steroids, tannins, alkaloids, terpenes, etc. Syzygium aromaticum (clove) is a traditional spice that has been used for food preservation and possesses various pharmacological activities. S. aromaticum is rich in many phytochemicals as follows: sesquiterpenes, monoterpenes, hydrocarbon, and phenolic compounds. Eugenyl acetate, eugenol, and β-caryophyllene are the most significant phytochemicals in clove oil. Pharmacologically, S. aromaticum has been examined toward various pathogenic parasites and microorganisms, including pathogenic bacteria, Plasmodium, Babesia, Theileria parasites, Herpes simplex, and hepatitis C viruses. Several reports documented the analgesic, antioxidant, anticancer, antiseptic, anti-depressant, antispasmodic, anti-inflammatory, antiviral, antifungal, and antibacterial activity of eugenol against several pathogenic bacteria including methicillin-resistant Staphylococcus epidermidis and S. aureus. Moreover, eugenol was found to protect against CCl₄₋induced hepatotoxicity and showed a potential lethal efficacy against the multiplication of various parasites including Giardia lamblia, Fasciola gigantica, Haemonchus contortus, and Schistosoma mansoni. This review examines the phytochemical composition and biological activities of clove extracts along with clove essential oil and the main active compound, eugenol, and implicates new findings from gas chromatography-mass spectroscopy (GC-MS) analysis.

Berberis vulgaris (B. vulgaris) and Rhus coriaria (R. coriaria) have been documented to have various pharmacologic activities. The current study assessed the in vitro as well as in vivo inhibitory efficacy of a methanolic extract of B. vulgaris (MEBV) and an acetone extract of R. coriaria (AERC) on six species of piroplasm parasites. The drug-exposure viability assay was tested on three different cell lines, namely mouse embryonic fibroblast (NIH/3T3), Madin-Darby bovine kidney (MDBK) and human foreskin fibroblast (HFF) cells. Qualitative phytochemical estimation revealed that both extracts containing alkaloid, tannin, saponins and terpenoids and significant amounts of flavonoids and polyphenols. The GC-MS analysis of MEBV and AERC revealed the existence of 27 and 20 phytochemical compounds, respectively. MEBV and AERC restricted the multiplication of Babesia (B.) bovis, B. bigemina, B. divergens, B. caballi, and Theileria (T.) equi at the half-maximal inhibitory concentration (IC₅₀) of 0.84 ± 0.2, 0.81 ± 0.3, 4.1 ± 0.9, 0.35 ± 0.1 and 0.68 ± 0.1 µg/mL and 85.7 ± 3.1, 60 ± 8.5, 90 ± 3.7, 85.7 ± 2.1 and 78 ± 2.1 µg/mL, respectively. In the cytotoxicity assay, MEBV and AERC inhibited MDBK, NIH/3T3 and HFF cells with half-maximal effective concentrations (EC₅₀) of 695.7 ± 24.9, 931 ± 44.9, >1500 µg/mL and 737.7 ± 17.4, >1500 and >1500 µg/mL, respectively. The experiments in mice showed that MEBV and AERC prohibited B. microti multiplication at 150 mg/kg by 66.7% and 70%, respectively. These results indicate the prospects of these extracts as drug candidates for piroplasmosis treatment following additional studies in some clinical cases.

Background: The antiprotozoal and antioxidant activities of Viola tricolor and Laurus nobilis have been reported recently. Thus, the existing study pursued to assess the growth inhibition effect of methanolic extract of V. tricolor (MEVT) and acetonic extract of L. nobilis (AELN) against five Babesia parasites and Theileria equi in vitro and in vivo. Results: MEVT and AELN suppressed Babesia bovis, B. bigemina, B. divergens, B. caballi, and T. equi growth at half-maximal inhibitory concentration (IC₅₀) values of 75.7 ± 2.6, 43.3 ± 1.8, 67.6 ± 2.8, 48 ± 3.8, 54 ± 2.1 μg/mL, and 86.6 ± 8.2, 33.3 ± 5.1, 62.2 ± 3.3, 34.5 ± 7.5 and 82.2 ± 9.3 μg/mL, respectively. Qualitative phytochemical estimation revealed that both extracts containing multiple bioactive constituents and significant amounts of flavonoids and phenols. The toxicity assay revealed that MEVT and AELN affected the mouse embryonic fibroblast (NIH/3 T3) and Madin–Darby bovine kidney (MDBK) cell viability with half-maximum effective concentrations (EC₅₀) of 930 ± 29.9, 1260 ± 18.9 μg/mL, and 573.7 ± 12.4, 831 ± 19.9 μg/mL, respectively, while human foreskin fibroblasts (HFF) cell viability was not influenced even at 1500 μg/mL. The in vivo experiment revealed that the oral administration of MEVT and AELN prohibited B. microti multiplication in mice by 35.1 and 56.1%, respectively. Conclusions: These analyses indicate the prospects of MEVT and AELN as good candidates for isolating new anti-protozoal compounds which could assist in the development of new drug molecules with new drug targets.

Medicinal plants have been documented as an important source for discovering new pharmaceutical molecules that have been used to treat serious diseases. Strikingly, previous reports stated that natural products and their derived compounds exhibit lesser side effects and improved efficacy than other synthetic counterparts. Physostigmine, a parasympathomimetic plant alkaloid isolated from the West African perennial shrub Physostigma venenosum, it shows a narrow therapeutic index and a short life span, despite its ability to penetrate the blood-brain barrier (BBB). It is a widely known reversible butyrylcholinesterase (BuChE) and acetylcholinesterase (AChE) inhibitor and has been documented to treat various ailments such as Alzheimer’s disease. Pharmacologically, physostigmine was first reported as an antidote for atropine scopolamine and belladonna alkaloids toxicity. Recently, it has been documented as a therapy for treating several ailments including glaucoma, myasthenia gravis and the intoxication caused by tricyclic antidepressant overdoses, anti-histamines, antipsychotics, and benzodiazepines. Physostigmine has been reported to be absorbed from the gastrointestinal tract and showed short half-life, as, after the oral administration of 2 mg of physostigmine salicylate, the peak plasma concentration reached to 30 minutes. This review examines the biological activities, pharmacokinetics, and toxicity of physostigmine extracted from P. venenosum. Keywords: Physostigma venenosum, Physostigmine, pharmacological activities, acetylcholinesterase and butyrylcholinesterase inhibitor.

Type 2 diabetes mellitus (T2DM) is a potential risk factor for the development of COVID-19 and is associated with higher severity and mortality rates. T2DM patients are commonly treated with metformin monotherapy or metformin plus sitagliptin. In the present case-control, single-center cohort study, a total number of 112 T2DM patients suffering from COVID-19 and aged 44–62 years old were compared with 78 T2DM patients without COVID-19 and aged 42–56 years old. Both the patient group and the control group were allocated into four groups. Group A: T2DM patients with COVID-19 on metformin treatments plus standard therapy (n = 60); group B: T2DM patients with COVID-19 on metformin plus sitagliptin plus standard therapy (n = 52); group C: T2DM patients without COVID-19 on metformin treatments (n = 40); and group D: T2DM patients without COVID-19 on metformin plus sitagliptin (n = 38). The investigation duration was 2–3 weeks. Anthropometric measurements, serological and biochemical investigations, pulmonary radiological findings, and clinical outcomes were evaluated. Only 101 T2DM patients with COVID-19 continued the study, 71 (70.29%) with mild-moderate COVID-19 and 30 (29.7%) with severe COVID-19 were compared with 78 T2DM patients as a control. Inflammatory biomarkers (C reactive protein, ferritin, and procalcitonin), a lung injury biomarker (lactate dehydrogenase), and a coagulopathy biomarker (D-dimer) were elevated in severe COVID-19 patients compared with mild-moderate COVID-19 (p < 0.05) and T2DM patients (p < 0.05). However, metformin plus sitagliptin was more effective than metformin monotherapy in T2DM patients with COVID-19, as evidenced by the mitigation of oxidative stress, CT scan score, and clinical outcomes. The present study confirmed the protective effects of this combination against the development of COVID-19 severity, as most T2DM COVID-19 patients develop mild-moderate forms. Herein, the combination of metformin and sitagliptin may lead to more beneficial effects than metformin monotherapy.

Insulin resistance and diabetes are associated with non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) conditions, which are distinguished by metabolic dysfunction, oxidative stress and inflammation. Sirtuin 1 (SIRT1), a NAD⁺-dependent deacetylase, is fundamental in regulating metabolic pathways, reducing inflammation, and improving antioxidant defenses. This is the first study to investigate the effects of SRT1720, a SIRT1 activator, in diabetic rats on a high-fat diet. SRT1720 significantly lowered fasting blood glucose and insulin levels and enhanced glucose tolerance and HOMA-IR and QUICKI scores, indicating increased insulin sensitivity. The treatment also reduced total cholesterol, triglycerides, and LDL levels, showing amelioration of dyslipidemia. Moreover, SRT1720 lowered markers of liver fibrosis, including TGF-β, TIMP-1, Col1a1, and hydroxyproline, and decreased inflammation by reducing NFκB activity and pro-inflammatory cytokines (TNF-α and IL-6). Furthermore, SRT1720 augmented Nrf2 activity and HO-1 levels. Consequently, the SRT1720's protective role improved liver function and histology and prolonged rats' survival. These functions were suppressed by the co-administration of the SIRT1 inhibitor EX527, confirming that the beneficial effects of SRT1720 are SIRT1-dependent. Correlation analyses uncovered that increased SIRT1 activity was strongly associated with decreased oxidative stress, inflammation, insulin resistance, and fibrosis markers. To conclude, our results find that SRT1720 represents a promising therapeutic strategy for managing Type 2 diabetes in NAFLD or NASH patients possibly through the modulation of the SIRT1/Nrf2/NFκB signaling pathwa. SRT1720 could potentially halt or reverse the progression of these conditions and associated complications and merits further investigations.