Role of Omega-3 Fatty Acids as Non-Photic Zeitgebers and Circadian Clock Synchronizers

Docosahexaenoic Acid and Sleep Quality in Very and Extreme Preterm Infants

The results regarding the association of plasma docosahexaenoic acid (DHA) levels with sleep duration conflict. This study aimed to investigate the effect of oral administration of DHA on the sleep quality of Brazilian extreme preterm infants. This cohort study is part of the Joinville Docosahexaenoic Acid Study (JoiDHA) conducted with 59 infants in Joinville, Brazil. Sleep quality was assessed using the Brief Infant Sleep Questionnaire, which consists of 12 questions about the quality of sleep the week prior to its application and was answered by the parents/guardians. Of the 59 children who participated in the study, 37 (62.7%) were supplemented with DHA and 22 (37.3%) did not receive DHA. The prevalence of poor sleep quality was higher among children with the weight status at birth <50th percentile (68.2%; p = 0.045) when compared to children ≥50th percentile. However, Poisson regression analysis showed that neither weight status at birth nor DHA use was associated with sleep quality, even after adjusting for the same variables. In summary, sleep quality 12-24 months after birth was not associated with DHA supplementation in very and extreme preterm infants. Additional studies that address the increase in DHA intake would be important for the understanding of the effect of this fatty acid on sleep quality.

Histology, fatty acid composition, antioxidant and glycolipid metabolism, and transcriptome analyses of the acute cold stress response in Phoxinus lagowskii

Water temperature is a crucial environmental factor that significantly affects the physiological and biochemical processes of fish. Due to the occurrence of cold events in aquaculture, it is imperative to investigate how fish respond to cold stress. This study aims to uncover the mechanisms responds to acute cold stress by conducting a comprehensive analysis of the histomorphology, glycolipid metabolic and antioxidant enzymes, fatty acid composition and transcriptome at three temperatures (16 °C, 10 °C and 4 °C) in Phoxinus lagowskii. Our results showed that cold stress not damaged muscle microstructure but caused autophagy (at 10 °C). In addition, serum glucose (Glu) and triglycerides (TG) increased during cold stress. The activities of reactive oxygen species (ROS), superoxide dismutase (SOD), catalase (CAT), fructose phosphokinase (PFK), hexokinase (HK), pyruvate kinase (PK), and malondialdehyde (MDA) content in muscle were measured and analyzed. During cold stress, superoxide dismutase and catalase activities increased, reactive oxygen species content decreased. No significant difference in Glutathione peroxidase (GPx) activity, malondialdehyde and total cholesterol (T-CHO) contents among groups. Phosphokinase and pyruvate kinase activities decreased, and HK activity increased during cold stress. Our study resulted in the identification of a total of 25,400 genes, with 2524 genes showing differential expression across different temperature treatments. Furthermore, KEGG pathway indicated that some pathways upregulated during light cold stress (at 10 °C, including autophagy, and AMP-activated protein kinase (AMPK) signaling pathway. Additionally, circadian rhythm is among the most enriched pathways in genes up-regulated during severe cold stress (at 4 °C). Our findings offer valuable insights into how cold-water fish respond to cold stress.

Nutrition as the foundation for successful aging: a focus on dietary protein and omega-3 polyunsaturated fatty acids

Skeletal muscle plays a critical role throughout the aging process. People living with sarcopenia, a progressive and generalized loss of skeletal muscle mass and function, often experience diminished quality of life, which can be attributed to a long period of decline and disability. Therefore, it is important to identify modifiable factors that preserve skeletal muscle and promote successful aging (SA). In this review, SA was defined as (1) low cardiometabolic risk, (2) preservation of physical function, and (3) positive state of wellbeing, with nutrition as an integral component. Several studies identify nutrition, specifically high-quality protein (eg, containing all essential amino acids), and long-chain omega-3 polyunsaturated fatty acids (n-3 PUFAs), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), as positive regulators of SA. Recently, an additive anabolic effect of protein and n-3 PUFAs has been identified in skeletal muscle of older adults. Evidence further suggests that the additive effect of protein and n-3 PUFAs may project beyond skeletal muscle anabolism and promote SA. The key mechanism(s) behind the enhanced effects of intake of protein and n-3 PUFAs needs to be defined. The first objective of this review is to evaluate skeletal muscle as a driver of cardiometabolic health, physical function, and wellbeing to promote SA. The second objective is to examine observational and interventional evidence of protein and n-3 PUFAs on skeletal muscle to promote SA. The final objective is to propose mechanisms by which combined optimal intake of high-quality protein and n-3 PUFAs likely play a key role in SA. Current evidence suggests that increased intake of protein above the Recommended Dietary Allowance and n-3 PUFAs above the Dietary Guidelines for Americans recommendations for late middle-aged and older adults is required to maintain skeletal muscle mass and to promote SA, potentially through the mechanistical target of rapamycin complex 1 (mTORC1).

Impacts of Omega-3 Fatty Acids, Natural Elixirs for Neuronal Health, on Brain Development and Functions

Omega-3 fatty acids play a seminal role in maintaining the structural and functional integrity of the nervous system. These specialized molecules function as precursors for many lipid-based biological messengers. Also, studies suggest the role of these fatty acids in regulating healthy sleep cycles, cognitive ability, brain development, etc. Dietary intake of essential poly unsaturated fatty acids (PUFA) such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are foundational to the optimal working of the nervous system. Besides regulating health, these biomolecules have great therapeutic value in treating several diseases, particularly nervous system diseases and disorders. Many recent studies conclusively demonstrated the beneficial effects of Omega-3 fatty acids in treating depression, neuropsychiatric disorders, neurodegenerative disorders, neurochemical disorders, and many other illnesses associated with the nervous system. This chapter summates the multifaceted role of poly unsaturated fatty acids, especially Omega-3 fatty acids (EPA and DHA), in the neuronal health and functioning. The importance of dietary intake of these essential fatty acids, their recommended dosages, bioavailability, the mechanism of their action, and therapeutic values are extensively discussed.

Circadian Rhythm Regulator REV-ERBα Attenuates Neuroapoptosis in Early Brain Injury After Experimental Subarachnoid Hemorrhage in Rats

Subarachnoid hemorrhage (SAH) is associated with circadian rhythm abnormalities, in which REV-ERBα plays a major regulatory role. Our ambition was to investigate the capacity of REV-ERBα to inhibit neuronal neuroapoptosis induced by early brain injury (EBI) after SAH. The endovascular perforation model was used to produce experimental SAH in Sprague-Dawley rats. Specific small-interfering RNA was used to downregulate the expression REV-ERBα while SR9009 was used to upregulate the expression before assessments. Short- and long-term neurobehavior assessments, immunofluorescence staining, TUNEL staining, Nissl staining, brain water content, and Western blot were performed. The expression level of endogenous REVERBα tended to increase and then decrease after SAH and peaked at 48 h. REV-ERBα upregulation diminished neuronal apoptosis and enhanced neurological function deficits. Meanwhile, REV-ERBα downregulation aggravated the damage. Furthermore, the levels of downstream proteins of REV-ERBα (i.e., brain and muscle ARNT-like 1 (BMAL1) and circadian locomotor output cycles kaput (CLOCK)) changed accordingly with REV-ERBα regulation. REV-ERBα may attenuate neuronal apoptosis in EBI after SAH through the BMAL1/CLOCK pathway.