Dietary zinc inadequacy affects neurotrophic factors and proteostasis in the rat brain.

Zinc (Zn) deficiency has many adverse effects, including growth retardation, loss of appetite, vascular diseases, cognitive and memory impairment, and neurodegenerative diseases. In the current study, we investigated the hypothesis that dietary Zn inadequacy affects neurotrophic factors and proteostasis in the brain. Three-week-old Wistar/Kyoto male rats were fed either a Zn-deficient diet (D; < 1 mg Zn/kg diet; n = 18) or pair-fed with the control diet (C; 48 mg Zn/kg diet; n = 9) for 4 weeks. Subsequently, the rats in the D group were subdivided into two groups (n = 9), in which one group continued to receive a Zn-deficient diet, whereas the other received a Zn-supplemented diet (R; 48 mg Zn/kg diet) for 3 more weeks, after which the rats were sacrificed to collect their brain tissue. Markers of endoplasmic reticulum stress, ubiquitin-proteasome system, autophagy, and apoptosis, along with neurotrophic factors, were investigated by immunoblotting. Proteasomal activity was analyzed by the spectrofluorometric method. The results showed an altered ubiquitin-proteasome system and autophagy components and increased gliosis, endoplasmic reticulum stress, and apoptosis markers in Zn-deficient rats compared with the control group. Zinc repletion for 3 weeks could partially restore these alterations, indicating a necessity for an extended duration of Zn supplementation. In conclusion, a decline in Zn concentrations below a critical threshold may trigger multiple pathways, leading to brain-cell apoptosis.

Combined prenatal to postnatal protein restriction augments protein quality control processes and proteolysis in the muscle of rat offspring.

Several human epidemiological and animal studies suggest that a maternal low-protein (MLP) diet affects skeletal muscle (SM) health in the offspring. However, effect of combined prenatal to postnatal protein restriction (chronic PR) and prenatal to perinatal protein restriction (PR) with postnatal rehabilitation maternal protein restriction (MPR) on protein quality control (PQC) processes and proteolysis in the offspring remains poorly understood. The current study explored the impact of chronic PR and MPR on SM protein degradation rates, chaperones, unfolded protein response (UPR), ubiquitin-proteasome system (UPS), autophagy, and apoptosis, in the adult offspring. Wistar rats were randomly assigned to a normal protein (NP; 20% casein), or low-protein (LP; 8% casein) isocaloric diets from 7 weeks prior to breeding through weaning. Offspring born to NP dams received the same diet (NP offspring) while a group of LP offspring remained on LP diet and another group was rehabilitated with NP diet (LPR offspring) from weaning for 16 weeks. LP offspring displayed lower body weight, lean mass, and myofiber cross-sectional area than NP. Furthermore, LP offspring demonstrated increased total protein degradation, urinary 3-methyl histidine, ER stress, autophagy, UPS components, proteasomal activity, muscle atrophy markers, and apoptosis-related proteins than NP. However, MPR showed little or no effect on muscle proteolysis, UPR, UPS, autophagy, apoptosis, and muscle atrophy in LPR offspring. These results indicate that exposure to chronic PR diets induces muscle atrophy and accelerates SM proteolysis via augmenting PQC processes in the offspring, while MPR shows little or no effect.

Highly efficient Agrobacterium-mediated transformation and plant regeneration system for genome engineering in tomato.

Tomato (Solanum lycopersicum L.) is an important vegetable and nutritious crop plant worldwide. They are rich sources of several indispensable compounds such as lycopene, minerals, vitamins, carotenoids, essential amino acids, and bioactive polyphenols. Plant regeneration and Agrobacterium-mediated genetic transformation system from different explants in various genotypes of tomato are necessary for genetic improvement. Among diverse plant growth regulator (PGR) combinations and concentrations tested, Zeatin (ZEA) at 2.0 mg l-1 in combination with 0.1 mg l-1 indole-3-acetic acid (IAA) generated the most shoots/explant from the cotyledon of Arka Vikas (36.48 shoots/explant) and PED (24.68 shoots/explant), respectively. The hypocotyl explant produced 28.76 shoots/explant in Arka Vikas and 19.44 shoots/explant in PED. In contrast, leaf explant induced 23.54 shoots/explant in Arka Vikas and 17.64 shoots/explant in PED. The obtained multiple shoot buds from three explant types were elongated on a medium fortified with Gibberellic acid (GA3) (1.0 mg l-1), IAA (0.5 mg l-1), and ZEA (0.5 mg l-1) in both the cultivars. The rooting was observed on a medium amended with 0.5 mg l-1 indole 3-butyric acid (IBA). The transformation efficiency was significantly improved by optimizing the pre-culture of explants, co-cultivation duration, bacterial density and infection time, and acetosyringone concentration. The presence of transgenes in the plant genome was validated using different methods like histochemical GUS assay, Polymerase Chain Reaction (PCR), and Southern blotting. The transformation efficiency was 42.8% in PED and 64.6% in Arka Vikas. A highly repeatable plant regeneration protocol was established by manipulating various plant growth regulators (PGRs) in two tomato cultivars (Arka Vikas and PED). The Agrobacterium-mediated transformation method was optimized using different explants like cotyledon, hypocotyl, and leaf of two tomato genotypes. The present study could be favourable to transferring desirable traits and precise genome editing techniques to develop superior tomato genotypes.

Chronic Effects of Maternal Low-Protein and Low-Quality Protein Diets on Body Composition, Glucose-Homeostasis and Metabolic Factors, Followed by Reversible Changes upon Rehabilitation in Adult Rat Offspring.

Several studies suggest that the maternal protein content and source can affect the offspring's health. However, the chronic impact of maternal quality and quantity protein restriction, and reversible changes upon rehabilitation, if any, in the offspring, remains elusive. This study examined the effects of maternal low-quality protein (LQP) and low-protein (LP) intake from preconception to post-weaning, followed by rehabilitation from weaning, on body composition, glucose-homeostasis, and metabolic factors in rat offspring. Wistar rats were exposed to normal protein (NP; 20% casein), LQP (20% wheat gluten) or LP (8% casein) isocaloric diets for 7 weeks before pregnancy until lactation. After weaning, the offspring were exposed to five diets: NP, LQP, LQPR (LQP rehabilitated with NP), LP, and LPR (LP rehabilitated with NP) for 16 weeks. Body composition, glucose-homeostasis, lipids, and plasma hormones were investigated. The LQP and LP offspring had lower bodyweight, fat and lean mass, insulin and HOMA-IR than the NP. The LQP offspring had higher cholesterol, T3 and T4, and lower triacylglycerides and glucose, while these were unaltered in LP compared to NP. The majority of the above outcomes were reversed upon rehabilitation. These results suggest that the chronic exposure of rats to maternal LQP and LP diets induced differential adverse effects by influencing body composition and metabolism, which were reversed upon rehabilitation.