Estrogen-mediated mitigation of cardiac oxidative stress in ovariectomized rats is associated with upregulated cardiac circadian clock Per2 and heart-specific miRNAs.

AIM: Estrogen (E2) confers cardioprotection in premenopausal women and in models of menopause and its effects, mostly studied in female reproductive organs, vary on a circadian rhythm basis in relation to the circadian clock genes. However, it remains unknown if a similar circadian pattern exists in the female heart in a manner that explains, at least partly, the cardioprotective effect of E2. The aim of the present investigation was to determine if upregulation of the circadian clock Per2 and its regulated heart-specific miRNAs, and redox enzymes contribute to the E2-mediated cardioprotection in ovariectomized rats. MAIN METHODS: Rats were subjected to ovariectomy (OVX) 2-weeks prior to a 2-week E2 treatment. On the last treatment day, hearts were collected every 4 h. for ex-vivo biochemical measurements. In parallel studies, telemetric mean arterial pressure (MAP) was obtained at the tissue collection times. KEY FINDINGS: OVX + E2 rats exhibited lower body weight during daytime and MAP during day and night times, and their hearts exhibited: (1) higher Per2 protein abundance, cardioprotective miRNAs (miRNA1, miRNA133a, miRNA208a, miRNA499), mALDH2, and catalase; (2) lower reactive oxygen species, cardio-detrimental miRNA652, carbonyl, MDA and HO-1 levels. The reciprocal Per2/HO-1 relationship was more evident during the daytime and correlated with the upregulated cardioprotective miRNAs in OVX + E2 rats. Finally, cardiac Per2, heart-specific miRNAs and reactive oxygen species levels and redox enzymes activities were similar in normal female and OVX + E2 rats. SIGNIFICANCE: Enhancement of cardiac Per2, redox enzymes and heart-specific miRNAs likely contribute to E2-mediated mitigation of cardiac oxidative stress in OVX rats.

Approaches for prevention and environmental management of novel COVID-19.

The World Health Organization (WHO) recognized a novel coronavirus as the causative agent of a new form of pneumonia. It was subsequently named COVID-19 and reported as the source of a respiratory disease occurrence starting in December 2019 in Wuhan, Hubei Province, China. It has been affirmed a public health emergency of international significance by the World Health Organization. It is regarded as a subset of the severe acute respiratory syndrome (SARS) and the Middle East respiratory syndrome (MERS); COVID-19 is triggered by a betacoronavirus called SARS-CoV-2, which affects the lower respiratory tract and occurs in humans as pneumonia. A variety of drugs, such as remdesivir and favipiravir, are currently undergoing clinical trials to evaluate for the management of COVID-19. The effect of the pandemic as well as the epidemic that follows through the life cycles of various recycled plastic is evaluated, particularly those required for personal safety and health care. In response to the growth in COVID-19 cases worldwide, the energy and environmental impacts of these lifecycle management have risen rapidly. However, significant hazardous waste management concerns arise due to the need to assure the elimination of residual pathogens in household and medical wastes. This review article summarizes the preventive and environmental management of COVID-19.