Increased panicle nitrogen application improves rice yield by alleviating high-temperature damage during panicle initiation to anther development.

The grain yield is closely associated with spikelet fertility in rice (Oryza sativa L.) under high temperatures, and nitrogen (N) plays a crucial role in yield formation. To investigate the effect of panicle N application on yield formation under high temperatures at the panicle initiation stage, two rice varieties [Liangyoupeijiu (LYPJ, heat susceptible) and Shanyou63 (SY63, heat tolerant)] were grown and exposed to high daytime temperature (HT) and control temperature (Control) during the panicle initiation stage. Low (LPN) and high (HPN) panicle N applications were conducted. HT markedly decreased the yields by 87% at LPN and 48% at HPN in LYPJ and 31% at LPN and 36% at HPN in SY63. The decrease in grain yield under HT was primarily attributed to the decline in spikelet fertility, HPN increased spikelet fertility. HT resulted in the abnormal development of anthers, which included disordered, enlarged, and broken anther wall layers, degraded and irregularly shaped microspores, delayed tapetum degradation, less vacuolated microspores per locule, abnormal and aborted pollen grains; however, HPN improved the development of anthers under HT, particularly in LYPJ. A high rate of evapotranspiration resulted in an approximately 1°C decrease in panicle temperatures at HPN compared with that at LPN in both varieties under HT. Overall, these results demonstrate that the increased panicle N application favors normal anther development in LYPJ by decreasing the panicle temperature, which results in high pollen viability and spikelet fertility, and consequently less yield loss under HT.

S-adenosylmethionine improves cognitive impairment in D-galactose-induced brain aging by inhibiting oxidative stress and neuroinflammation.

Oxidative stress and neuroinflammation play crucial roles in aging. S-adenosylmethionine (SAM), a popular supplement, is a potential antioxidant and candidate therapy for depression. This study aimed to evaluate the neuroprotective effects of SAM on D-galactose-induced brain aging and explore its underlying mechanisms. Brain aging model was established with D-galactose (180 mg/kg/day) for 8 weeks. During the last 4 weeks, SAM (16 mg/kg) was co-administrated with D-galactose. Behavior tests were used to assess cognitive function and depression-like behaviors of rats. Results showed that cognitive impairment and depression-like behaviors were reversed by SAM. SAM reduced neuronal cell loss, increased brain-derived neurotrophic factor level in the hippocampus, inhibited amyloid-ß level and microglia activation, as well as pro-inflammatory factors levels in the hippocampus and serum. Further, SAM enhanced antioxidant capacity and attenuated cholinergic damage by reducing malondialdehyde levels, increasing acetylcholine levels, expression levels of α7 nicotinic acetylcholine receptor (α7nAChR), nuclear factor erythrocyte 2-related factor 2 (Nrf2) and heme oxygenase 1 (HO-1) in the hippocampus. Above all, SAM has a potential neuroprotective effect on ameliorating cognitive impairment in brain aging, which is related to inhibition of oxidative stress and neuroinflammation, as well as α7nAChR signals. DATA AVAILABILITY: Data will be made available on request.

Effects of aqueous extract of Arctium lappa L. roots on serum lipid metabolism.

Objective To identify potential genes that may be involved in lipid metabolism in rats after treatment with aqueous extract of Arctium lappa L (burdock). Methods Rats were randomly divided into six groups: (i) control (standard diet); (ii) model group (high-fat diet only); (iii) high-fat diet and low-dose aqueous burdock root extract (2 g/kg); (iv) high-fat diet and moderate-dose aqueous burdock root extract (4 g/kg); (v) high-fat diet and high-dose aqueous burdock root extract (8 g/kg); and (vi) a positive control group exposed to a high-fat diet and simvastatin (10 mg/kg). Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis was performed to find the potential candidate genes involved in the modulation of blood lipids by treatment with aqueous burdock root extract. Results Burdock root extract reduced body weight and cholesterol levels in rats. KEGG analysis revealed 113 genes that were involved in metabolic pathways. Of these, 27 potential genes associated with blood lipid metabolism were identified. Conclusions Aqueous extract of burdock root reduced body weight and cholesterol in rats, possibly by modulating the differential expression of genes.

Improved Anticancer Photothermal Therapy Using the Bystander Effect Enhanced by Antiarrhythmic Peptide Conjugated Dopamine-Modified Reduced Graphene Oxide Nanocomposite.

Despite tremendous efforts toward developing novel near-infrared (NIR)-absorbing nanomaterials, improvement in therapeutic efficiency remains a formidable challenge in photothermal cancer therapy. This study aims to synthesize a specific peptide conjugated polydopamine-modified reduced graphene oxide (pDA/rGO) nanocomposite that promotes the bystander effect to facilitate cancer treatment using NIR-activated photothermal therapy. To prepare a nanoplatform capable of promoting the bystander effect in cancer cells, we immobilized antiarrhythmic peptide 10 (AAP10) on the surface of dopamine-modified rGO (AAP10-pDA/rGO). Our AAP10-pDA/rGO could promote the bystander effect by increasing the expression of connexin 43 protein in MCF-7 breast-cancer cells. Because of its tremendous ability to absorb NIR absorption, AAP10-pDA/rGO offers a high photothermal effect under NIR irradiation. This leads to a massive death of MCF-7 cells via the bystander effect. Using tumor-bearing mice as the model, it is found that NIR radiation effectively ablates breast tumor in the presence of AAP10-pDA/rGO and inhibits tumor growth by ≈100%. Therefore, this research integrates the bystander and photothermal effects into a single nanoplatform in order to facilitate an efficient photothermal therapy. Furthermore, our AAP10-pDA/rGO, which exhibits both hyperthermia and the bystander effect, can prevent breast-cancer recurrence and, therefore, has great potential for future clinical and research applications.