Anti-inflammatory and antioxidant activities of methanol extract of Piper betle Linn. (Piper betle L.) leaves and stems by inhibiting NF-κB/MAPK/Nrf2 signaling pathways in RAW 264.7 macrophages.

Oxidative stress and chronic inflammation are closely linked to various diseases. However, previous studies have demonstrated that plant extracts could prevent and alleviate these adverse outcomes. Piper betle Linn. (Piper betle L.) is a cosmopolitan plant that belongs to the Piperaceae family, whose leaves are edible and possess several health benefits. This study sought to characterize the anti-inflammatory and antioxidant effects of a methanol extract of Piper betle L. leaves and stems (MPBLLS). MPBLLS was found to have a dose-dependent radical scavenging effect, as demonstrated by the 2,2-diphenyl-1-picrylhydrazyl assay. Additionally, MPBLLS inhibited the lipopolysaccharide (LPS)-stimulated production of nitric oxide and prostaglandin E2 by reducing the expression of inducible nitric oxide synthase and cyclooxygenase-2 in RAW 264.7 macrophages without affecting cell viability. Furthermore, our findings suggested that the inhibitory effects of MPBLLS on pro-inflammatory cytokines such as tumor necrosis factor-α, interleukin-1ß, and interleukin-6 were due to the inhibition of the nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways in LPS-treated RAW 264.7 macrophages. MPBLLS and hydroxychavicol, a major constituent of MPBLLS, suppressed LPS-induced translocation of NF-κB p65 from cytoplasm to nucleus. Interestingly, MPBLLS increased nuclear factor erythroid 2-related factor 2 (Nrf2) protein levels and transcription levels of Nrf2 target genes in a dose-dependent manner. Collectively, our findings suggest that MPBLLS could serve as a basis for the development of novel orally-administered therapies due to its inhibitory effects on oxidative and inflammatory stress. DATA AVAILABILITY: The data presented in this study are available on request from the corresponding author.

Phenology and Seed Yield Performance of Determinate Soybean Cultivars Grown at Elevated Temperatures in a Temperate Region.

Increased temperature means and fluctuations associated with climate change are predicted to exert profound effects on the seed yield of soybean. We conducted an experiment to evaluate the impacts of global warming on the phenology and yield of two determinate soybean cultivars in a temperate region (37.27°N, 126.99°E; Suwon, South Korea). These two soybean cultivars, Sinpaldalkong [maturity group (MG) IV] and Daewonkong (MG VI), were cultured on various sowing dates within a four-year period, under no water-stress conditions. Soybeans were kept in greenhouses controlled at the current ambient temperature (AT), AT+1.5°C, AT+3.0°C, and AT+5.0°C throughout the growth periods. Growth periods (VE-R7) were significantly prolonged by the elevated temperatures, especially the R1-R5 period. Cultivars exhibited no significant differences in seed yield at the AT+1.5°C and AT+3.0°C treatments, compared to AT, while a significant yield reduction was observed at the AT+5.0°C treatment. Yield reductions resulted from limited seed number, which was due to an overall low numbers of pods and seeds per pod. Heat stress conditions induced a decrease in pod number to a greater degree than in seed number per pod. Individual seed weight exhibited no significant variation among temperature elevation treatments; thus, seed weight likely had negligible impacts on overall seed yield. A boundary line analysis (using quantile regression) estimated optimum temperatures for seed number at 26.4 to 26.8°C (VE-R5) for both cultivars; the optimum temperatures (R5-R7) for single seed weight were estimated at 25.2°C for the Sinpaldalkong smaller-seeded cultivar, and at 22.3°C for the Daewonkong larger-seeded cultivar. The optimum growing season (VE-R7) temperatures for seed yield, which were estimated by combining the two boundary lines for seed number and seed weight, were 26.4 and 25.0°C for the Sinpaldalkong and Daewonkong cultivars, respectively. Considering the current soybean growing season temperature, which ranges from 21.7 (in the north) to 24.6°C (in the south) in South Korea, and the temperature response of potential soybean yields, further warming of less than approximately 1°C would not become a critical limiting factor for soybean production in South Korea.

Identification of quantitative trait loci for cadmium accumulation and distribution in rice (Oryza sativa).

Cadmium (Cd) poses a serious risk to human health due to its biological concentration through the food chain. To date, information on genetic and molecular mechanisms of Cd accumulation and distribution in rice remains to be elucidated. We developed an independent F7 RIL population derived from a cross between two japonica cultivars with contrasting Cd levels, 'Suwon490' and 'SNU-SG1', for QTLs identification of Cd accumulation and distribution. 'Suwon490' accumulated five times higher Cd in grain than 'SNU-SG1'. Large genotypic variations in Cd accumulation (17-fold) and concentration (12-fold) in grain were found among RILs. Significant positive correlations between Cd accumulation in grain with shoot Cd accumulation and shoot to grain distribution ratio of Cd signify that both shoot Cd accumulation and shoot to grain Cd distribution regulate Cd accumulation in japonica rice grain. A total of five main effect QTLs (scc10 for shoot Cd accumulation; gcc3, gcc9, gcc11 for grain Cd accumulation; and sgr5 for shoot to grain distribution ratio) were detected in chromosomes 10, 3, 9, 11, and 5, respectively. Of these, the novel potential QTL sgr5 has the strongest effect on shoot to grain Cd distribution. In addition, two digenic epistatic interaction QTLs were identified, suggesting the substantial contribution of nonallelic genes in genetic control of these Cd-related traits.