A Preliminary Investigation on the Antiviral Activities of the Philippine Marshmint (Mentha arvensis) Leaf Extracts against Dengue Virus Serotype 2 In Vitro.

In this study, we investigated the antiviral activity of lyophilized crude leaf extracts of the Philippine marshmint (Mentha arvensis L., commonly called yerba buena) against DENV-2 in vitro. The plant specimen was authenticated by DNA barcoding analysis using standard primers for amplification of rbcL, matK, ITS1, ITS2 and trnH-psbA. Aqueous, methanol and ethanol leaf extracts were prepared, and lyophilized prior to testing for its cytotoxicity and antiviral activities. All extracts presented cytotoxic activities against Vero cells in a dose-dependent manner. Half maximal cytotoxicity concentration (CC50) was calculated at 2,889.60 µg/mL for the aqueous extract, 1,928.62 µg/mL for the methanol extract, and 3,380.30 µg/mL for the ethanol extract. Antiviral activities assessed by plaque reduction assay revealed reduced DENV-2 viral infectivity, with the ethanol extract observed to have the strongest activity decreasing plaque numbers by 62% relative to the control. The methanol extract was observed to be most effective when added before infection causing 72% reduction in plaque numbers, whereas none of the extracts inhibited plaque formation by more than 40% when added after infection. DENV-2 NS1 antigen production was significantly reduced by the methanol extract, while viral RNA levels were also decreased as determined by real time RT-PCR. Phytochemical analysis revealed the presence of flavonoids, phenolics, tannins, proteins, reducing sugars and saponins. Our preliminary results are promising, however, it should be interpreted with caution as further studies are needed to establish its potential therapeutic application against dengue infection.

Association of lipoprotein lipase gene polymorphisms with coronary artery disease among Filipinos.

Studies have shown association of lipoprotein lipase (LPL) polymorphisms with coronary artery disease (CAD); however, limited studies on the genetics of CAD have been done in the Philippines. Because of their effects on high-density lipoprotein and triglyceride metabolism, the G-allele of the Ser447X variant of LPL gene has been shown to be atheroprotective, while HindIII polymorphism has been shown to be pro-atherogenic. We assessed 1301 patients undergoing coronary angiography to determine the prevalence of HindIII and Ser447X polymorphisms and their association with angiographically significant CAD. Genotyping for HindIII and Ser447X variants were analyzed by real-time PCR. Multivariate analyses were performed to determine the interaction between LPL polymorphisms and risk factors of CAD. CAD+ group (72%) was predominantly male (76%) with a mean age of 60.17 ± 11.01 with hypertension (89%), dyslipidemia (84%) and smoking (54%) as the most common risk factors. HindIII carriage frequency among the CAD+ group was 20.3% with a genotypic distribution of 78.71% (T/T), 19.83% (T/G) and 1.46% (G/G). Ser447X carriage frequency among the CAD+ group was 8.0% with a genotypic distribution of 91.39% (C/C), 8.38% (C/G) and 0.23% (G/G). HindIII and Ser447X polymorphisms were both not significantly associated with CAD. LPL polymorphic allele HindIII was common, while Ser447X was rare. Present study did not show association of LPL polymorphisms with the development of CAD. However, among patients with dyslipidemia, presence of Ser447X allele is associated with an increased risk (OR 2.6; 95% CI 2.1-3.7; p value < 0.001) of developing CAD than those without LPL polymorphisms.