A long-term obesogenic high-fat diet in mice partially dampens the anti-frailty benefits of late-life intermittent fasting.

The global obesity pandemic coupled with ever-growing life expectancies equates to hundreds of millions of individuals with potentially longer but not healthier lives. Aging is one of the risk factors for numerous maladies such as metabolic disorder and frailty, which are exacerbated under obesity. Thus, therapeutic approaches that address obesity to ultimately improve affected individuals' quality of life and extend their lifespan are needed. We previously reported that the every other day (EOD) fasting initiated late-life improved metabolic, musculoskeletal, and cognitive endpoints in standard rodent diet-fed mice. In the present study, using the same dietary intervention methodology, we tested if 2.5 months of EOD fasting could improve metabolic, physiological, and cognitive endpoints in mice after an 18 month obesogenic high-fat diet (HFD). The positive effects of EOD fasting were generally consistent across the endpoints; EOD fasting decreased total body mass, maintained more %lean mass, improved glucose tolerance and utilization, and improved neuromuscular function. In contrast to our previous study, grip strength, hippocampal-dependent memory, and renal hydrogen sulfide (H2S) production were not improved by the HFD EOD fasting. Thus, efficacy for late-life initiated intermittent fasting to improve specific frailty markers may be partially dependent on nutritional compositions of the diet.

Osmoregulatory capacity of the shrimp Litopenaeus vannamei at different temperatures and salinities, and optimal culture environment

Osmoregulation in Litopenaeus vannamei was studied in a factorial experiment at four temperatures (20, 24, 28 and 32 degrees C) and six salinities (10, 16, 22, 28, 34 and 40 per thousand). The isosmotic related points for 20, 24, 28, and 32 degrees C were 754, 711, 822, and 763 mmol/kg, respectively. This species hyperregulates between at salinities of 10 and 20 per thousand and hyporegulates between 20 and 40 per thousand. The isosmotic point in L. vannamei exposed to constant salinities changed in relation to temperature from 717 to 823 mmol/kg. For these experimental conditions, the T-S combination of 32 degrees C and 28 per thousand produced the best growth.

La respuesta osmorreguladora de Litopenaeus vannamei se estudió en un experimento factorial con cuatro temperaturas (20, 24, 28 y 32 ºC) y seis salinidades (10, 16, 22, 28, 34 y 40 ‰). Los puntos isosmóticos relacionados para 20, 24, 28, y 32 ºC fueron 754, 711, 822, y 763 mmol/kg, respectivamente. Esta especie hiperregula dentro del intervalo de 10 y 20 ‰ e hiporegula entre 20 y 40 ‰. El punto isosmótico de L. vannamei expuesto a salinidades constantes cambia en relación a la temperatura desde 717 a 823 mmol/kg. Para estas condiciones experimentales, la combinación T-S de 32 ºC y 28 ‰ produjo el mejor crecimiento.

Osmoregulatory capacity of the shrimp Litopenaeus vannamei at different temperatures and salinities, and optimal culture environment.

Osmoregulation in Litopenaeus vannamei was studied in a factorial experiment at four temperatures (20, 24, 28 and 32 degrees C) and six salinities (10, 16, 22, 28, 34 and 40 per thousand). The isosmotic related points for 20, 24, 28, and 32 degrees C were 754, 711, 822, and 763 mmol/kg, respectively. This species hyperregulates between at salinities of 10 and 20 per thousand and hyporegulates between 20 and 40 per thousand. The isosmotic point in L. vannamei exposed to constant salinities changed in relation to temperature from 717 to 823 mmol/kg. For these experimental conditions, the T-S combination of 32 degrees C and 28 per thousand produced the best growth.