Introduction Vitamin D levels have been reported to be associated with COVID-19 susceptibility, severity, and mortality events. We performed a meta-analysis of randomized controlled trials (RCTs) to evaluate the use of vitamin D intervention on COVID-19 outcomes. Areas covered Literature search was conducted using PubMed, Cochrane library, and ClinicalTrials.gov databases. We included RCTs reporting the use of vitamin D intervention to control/placebo group in COVID-19. The study was registered at PROSPERO: CRD42021271461. Expert opinion A total of 6 RCTs with 551 COVID-19 patients were included. The overall collective evidence pooling all the outcomes across all RCTs indicated the beneficial use of vitamin D intervention in COVID-19 (relative risk, RR = 0.60, 95% CI 0.40 to 0.92, Z = 2.33, p = 0.02, I 2 = 48%). The rates of RT-CR positivity were significantly decreased in the intervention group as compared to the non-vitamin D groups (RR = 0.46, 95% CI 0.24 to 0.89, Z = 2.31, p = 0.02, I 2 = 0%). Conclusively, COVID-19 patients supplemented with vitamin D are more likely to demonstrate fewer rates of ICU admission, mortality events, and RT-PCR positivity.

This study was designed to investigate the protective effects of the centella triterpene saponins (EXT) on cyclophosphamide (CYP)-induced hepatotoxicity and immunosuppression in rats. The phytochemical profile of EXT was analyzed for centella saponins by using high-performance liquid chromatographic (HPLC). Therapeutic efficacy of EXT (250 mg/kg/day p.o) on hematological profile of blood, liver function markers, and cytokine profiles in CYP (10 mg/kg/day p.o)-treated rats. In addition, weights of immune organs (spleen and thymus) and histopathological changes in the liver, intestine, and spleen were also evaluated. The active principles in EXT were identified as madecassoside, asiaticoside, and asiatic acid by HPLC analysis. Upon administration of EXT, enhanced levels of glutamate pyruvate transaminase, alkaline phosphatase, and lipid peroxidation were found reduced while the levels of reduced glutathione and hematological parameters and relative weights of immune organs were restored to normal in CYP-treated rats. The hepatic mRNA level of TNF-α, which was increased during CYP administration, was significantly decreased by the EXT treatment. The decreased levels of mRNA expression of other cytokines like IFN-γ, IL-2, GM-CSF, after CYP treatment, were also found elevated upon administration of the EXT. Histopathological examination of the intestine, liver, and spleen indicated that the extract could attenuate the CYP-induced hepatic and immune organ damage. These results indicated that EXT modulated the immune and hepatic system function of rats against CYP-induced immunosuppression and hepatotoxicity by restoring the cytokine production, antioxidant system, and multiorgan injury. Thus, triterpene saponins may provide protective and/or therapeutic alternative against the immune-mediated liver diseases.

This meta-analysis, the first of its kind showed that the increased serum IMA concentrations were indicative of increased oxidative stress in NP and PE. Measurement of maternal serum IMA and fetal cord-blood IMA concentrations were useful as simple, novel, and inexpensive markers of oxidative stress (OS) status in PE patients. Future large-scale studies are needed to explore IMA in relationship to the disease severity in PE.

In the present investigation, we report simple, robust and eco-friendly synthesis of silver nanoparticles (AgNPs) using leaf extract of Flemingia wightiana. The leaf extract of F. wightiana acts as reducing agent which reduces the silver ions into FW-AgNPs, as well as stabilizing agent by capping around them. Biosynthesized FW-AgNPs were characterized by different spectroscopic techniques. UV-Vis spectrum showed the characteristic SPR peak between 380 and 460 nm. EDX analysis revealed the presence of metallic silver at 3 keV. XRD analysis clearly revealed that FW-AgNPs are crystalline in nature with FCC structure. TEM analysis depicted the spherical morphology with 20-40 nm in size. DLS analysis showed that average hydrodynamic size and PDI value of FW-AgNPs were found to be 47.6 nm and 4.5 respectively. Biosynthesized FW-AgNPs showed high negative zeta potential value of − 25.3 mV. FTIR analysis revealed the participation of polyphenols and proteins in the bioreduction and stabilization of FW-AgNPs. FW-AgNPs showed strong DPPH and H 2 O 2 scavenging activity with IC50 values of 71.96 and 80.59 µg/mL respectively. Further FW-AgNPs also showed effective cytotoxicity against cancer cells including SKOV3 and COLO205 with maximum inhibition of 83.2% and 75.9% respectively.

This meta-analysis showed IMA could be useful as a biomarker for PE with good accuracy (AUC = 0.860). However, further research is needed for re-evaluation and clinical validation of fairly promising results of this meta-analysis.