Maternal nutritional supplementation with fish oil and/or leucine improves hepatic function and antioxidant defenses, and minimizes cachexia indexes in Walker-256 tumor-bearing rats offspring

Walker-256 Tumour-Induced Cachexia Altered Liver Metabolomic Profile and Function in Weanling and Adult Rats

Cancer cachexia occurs in up to 85% of advanced cancer patients, affecting different tissues and organs, mainly the liver, which plays a central role in body metabolism control. However, liver responses to cancer cachexia progression are still poorly understood. Considering the possible different challenges provided by the rodent’s phase of life and the cachexia progression, we evaluated the liver metabolic alterations affected by Walker-256 tumour growth in weanling and young-adult rats. For this, we applied a metabolomics approach associated with protein and gene expression analyses. Higher amino acid levels and impaired glucose metabolism were important features in tumour-bearing animals’ liver tissue. The weanling hosts had more pronounced cachexia, with higher carcass spoliation, liver lipid metabolism and impaired CII and CIV mitochondrial complexes. The liver alterations in young adult tumour-bearing rats were related to energy status and nucleotide metabolites, such as uridine, NAD+, xanthosine, hypoxanthine and inosine. In conclusion, the Walker-256 tumour-induced cachexia impaired liver metabolism, being more severe in the weanling hosts. Further studies are needed to correlate these changes in the preclinical model, which can be correlated to the clinical features of cancer cachexia, allowing for a translational potential involving the liver function and its responses to potential treatments.

Pregnancy and Cancer: Cellular Biology and Mechanisms Affecting the Placenta

Cancer during pregnancy is rarely studied due to its low incidence (1:1000). However, as a result of different sociocultural and economic changes, women are postponing pregnancy, so the number of pregnant women with cancer has been increasing in recent years. The importance of studying cancer during pregnancy is not only based on maternal and foetal prognosis, but also on the evolutionary mechanisms of the cell biology of trophoblasts and neoplastic cells, which point out similarities between and suggest new fields for the study of cancer. Moreover, the magnitude of how cancer factors can affect trophoblastic cells, and vice versa, in altering the foetus's nutrition and health is still a subject to be understood. In this context, the objective of this narrative review was to show that some researchers point out the importance of supplementing branched-chain amino acids, especially leucine, in experimental models of pregnancy associated with women with cancer. A leucine-rich diet may be an interesting strategy to preserve physiological placenta metabolism for protecting the mother and foetus from the harmful effects of cancer during pregnancy.

Fish Oil Diet during Pre-mating, Gestation, and Lactation in Adult Offspring Rats on Cancer Cachexia Prevention

SCOPE

Nutritional supplementation of the maternal diet can modify the cancer susceptibility in adult offspring. Therefore, the authors evaluate the effects of a fish-oil diet administered to a long-term, during pre-mating, gestation, and lactation, in reducing cancer-cachexia damages in adult Walker-256 tumor-bearing offspring.

METHODS AND RESULTS

Female rats receive control or fish oil diet during pre-mating, gestation, and lactation. After weaning, male offspring are fed the control diet until adulthood and distributed in (C) control adult-offspring; (W) adult tumor-bearing offspring; (OC) adult-offspring of maternal fish oil diet; (WOC) adult tumor-bearing offspring of maternal fish oil diet groups. Fat body mass is preserved, muscle expression of mechanistic target of rapamicin (mTOR) and eukariotic binding protein of eukariotic factor 4E (4E-BP1) is modified, being associated with lower 20S proteasome protein expression, and the liver alanine aminotransferase (ALT) enzyme content maintained in the WOC group. Also, the OC group shows reduced triglyceridemia.

CONCLUSION

In this experimental model of cachexia, the long-term maternal supplementation is a positive strategy to improve liver function and lipid metabolism, as well as to modify muscle proteins expression in the mTOR pathway and also reduce the 20S muscle proteasome protein, without altering the tumor development and muscle wasting in adult tumor-bearing offspring.

Serum and Muscle 1H NMR-Based Metabolomics Profiles Reveal Metabolic Changes Influenced by a Maternal Leucine-Rich Diet in Tumor-Bearing Adult Offspring Rats

A maternal leucine-rich diet showed a positive effect on the gastrocnemius muscle of adult tumor-bearing offspring. To improve the understanding of the metabolic alterations of cancer cachexia and correlate this to preventive treatment, we evaluated the ¹H NMR metabolic profiles from serum and gastrocnemius muscle samples of adult Wistar rats. These profiles were initially analyzed, and chemometrics tools were applied to investigate the following groups: C, control group; W, tumor-bearing group; L, the group without tumors and with a maternal leucine-rich diet; WL, the tumor-bearing group with a maternal leucine-rich diet. Tumor growth that led to a high protein breakdown in the W group was correlated to serum metabolites such as tyrosine, phenylalanine, histidine, glutamine, and tryptophan amino acids and uracil. Also, decreased muscle lactate, inversely to serum content, was found in the W group. Conversely, in the WL group, increased lactate in muscle and serum profiles was found, which could be correlated to the maternal diet effect. The muscle lipidomics and NAD⁺, NADP⁺, lysine, 4-aminohippurate, and glutamine metabolites pointed to modified energy metabolism and lower muscle mass loss in the WL group. In conclusion, this exploratory metabolomics analyses provided novel insights related to the Walker-256 tumor-bearing offspring metabolism modified by a maternal leucine-rich diet and the next steps in its investigation.

A cascade extraction of active phycocyanin and fatty acids from Galdieria phlegrea

The setup of an economic and sustainable method to increase the production and commercialization of products from microalgae, beyond niche markets, is a challenge. Here, a cascade approach has been designed to optimize the recovery of high valuable bioproducts starting from the wet biomass of Galdieria phlegrea. This unicellular thermo-acidophilic red alga can accumulate high-value compounds and can live under conditions considered hostile to most other species. Extractions were performed in two sequential steps: a conventional high-pressure procedure to recover phycocyanins and a solvent extraction to obtain fatty acids. Phycocyanins were purified to the highest purification grade reported so far and were active as antioxidants on a cell-based model. Fatty acids isolated from the residual biomass contained high amount of PUFAs, more than those recovered from the raw biomass. Thus, a simple, economic, and high effective procedure was set up to isolate phycocyanin at high purity levels and PUFAs.

Maternal Leucine-Rich Diet Minimises Muscle Mass Loss in Tumour-bearing Adult Rat Offspring by Improving the Balance of Muscle Protein Synthesis and Degradation

Cachexia syndrome can affect cancer patients and new prevention strategies are required. Maternal nutritional supplementation can modify metabolic programming in the offspring, which lasts until adulthood. This could be a good approach against diseases such as cancer. A 3% leucine-rich diet treatment improved muscle protein turnover by modifying the mTOR and proteolytic pathways, thus we analysed whether maternal supplementation could ameliorate muscle protein turnover in adult offspring tumour-bearing rats. Pregnant Wistar rats received a control diet or 3% leucine-rich diet during pregnancy/lactation, and their weaned male offspring received a control diet until adulthood when they were distributed into following groups (n = 7–8 per group): C, Control; W, tumour-bearing; L, without tumour with a maternal leucine-rich diet; and WL, tumour-bearing with a maternal leucine-rich diet. Protein synthesis and degradation were assessed in the gastrocnemius muscle, focusing on the mTOR pathway, which was extensively altered in W group. However, the WL adult offspring showed no decrease in muscle weight, higher food intake, ameliorated muscle turnover, activated mTOR and p70S6K, and maintained muscle cathepsin H and calpain activities. Maternal leucine nutritional supplementation could be a positive strategy to improve muscle protein balance in cancer cachexia-induced muscle damage in adult offspring rats.