Somatopause, weaknesses of the therapeutic approaches and the cautious optimism based on experimental ageing studies with soy isoflavones

Biologia Futura: does the aging process contribute to the relativity of time?

In his Theory of relativity, Einstein determined that the time is relative to the reference frame of the observer. Under specific conditions, there is a difference in the elapsed time between two clocks, known as time dilation. A similar relativistic effect could be attributed to the brain operating at different frequencies, e.g., while it is slow and during the thought process. Time flow and the aging process are causally linked. Herein, we introduce physical relativity into the mind/thought context and elaborate changed perception of the time flow (the impression of the time acceleration) with aging. The phenomenology of time is observed in the context of physical and biological clock, as well as by introducing the category of 'mind time.' Mental processing impairment is crucial for the "aging-caused relativity of time," while adjusting of its' perception seems to be a matter of body/mind rest, mental hygiene and physical activity of the aging subject. We also provide a brief overview of the perception of time flow in some disease states that coincide with aging. Our main idea has a perspective for future development in the interdisciplinary synergy of philosophy, physical-mathematical elaboration, experimental biology and clinical investigations.

Citrus Flavanones Upregulate Thyrotroph Sirt1 and Differently Affect Thyroid Nrf2 Expressions in Old-Aged Wistar Rats

A growing population of elderly people consume citrus flavanones, naringenin, and hesperetin in the form of fruits or juices. Flavanones are bioactives with potent antioxidant properties and have potential in slowing down the aging process. Because flavanones exert controversial effects on pituitary-thyroid functioning, our study on the old-aged rat model aimed to elucidate the mechanism by which naringenin and hesperetin affect this axis. Naringenin and hesperetin increased the Sirt1 mRNA level by 91 and 71% (p < 0.05), which was followed by increased Sirt1 expression by 20 and 15% (p < 0.05), respectively. Only naringenin decreased thyroid-stimulating hormone expression by 20% (p < 0.05). Thyroid peroxidase protein expression was upregulated after naringenin or hesperetin by 62 and 43% (p < 0.05), respectively. Naringenin lowered mRNA levels of Tpo, Sod1, Sod2, Cat, and Nrf2 by 50, 32, 45, 35, and 42% (p < 0.05), respectively, and increased Gpx by 54% (p < 0.05), while hesperetin decreased Sod1 and Sod2 mRNA levels by 46 and 55% (p < 0.05), respectively. Naringenin increased the protein expressions of Nrf2 and SOD2 by 58 and 50% (p < 0.05), respectively, and decreased SOD1 expression by 48% (p < 0.05), while hesperetin protein decreased expressions of SOD1 and Nrf2 by 63 and 32% (p < 0.05), respectively. Altogether, our findings suggest that citrus flavanones contribute to restoring the impaired thyroid functioning in the old-aged rats.

Zhibaidihuang Decoction Ameliorates Cell Oxidative Stress by Regulating the Keap1-Nrf2-ARE Signalling Pathway

Zhibaidihuang decoction (ZBDHD) is a Chinese herbal formula, which is used in Chinese traditional medicine to treat symptoms of Yinxuhuowang (Yin deficiency and high fire) syndrome. This study elucidates the mechanism of ZBDHD on oral ulcers, one Yinxuhuowang syndrome. Simultaneously, some ingredients in ZBDHD were found and identified by ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). A Ganjiangfuzirougui decoction- (GJD-) induced Yinxuhuowang syndrome SD rat model was used to demonstrate the efficiency of ZBDHD treatment. The oral mucosa of rat in the GJD group, stained with hematoxylin and eosin (H&E), showed epidermal shedding and inflammatory cell infiltration. And an alleviation efficiency of ZBDHD in GJD-induced pathological changes in the oral mucosa could be obtained. ZBDHD treatment restored the GJD-induced imbalance of metabolites, which were choline, glycocholic acid, and palmitoyl-L-carnitine (PALC). GJD stimulated the expression of NF-κB. And the overexpressed of NF-κB in mucosa of rat in the GJD group could be inhibited by ZBDHD treatment. Simultaneously, the optimal efficiency of ZBDHD treatment on the cellular ATP content, oxygen consumption rate (OCR), and superoxide dismutase (SOD) concentration was evaluated, in vitro assay. Compared to the control cells, the ATP content, OCR, and SOD activity in the ZBDHD-treated cells were significantly higher. For the mechanisms study, seven cytokines were screened with a Dual-Luciferase Reporter gene assay. In the ARE assay, the luciferase signal was stimulated significantly by ZBDHD. In cells, the transcription of nrf2, maf, and keap1, which were related to the ARE pathway, was elevated by ZBDHD treatment. Our study demonstrated that high-dose GJD could lead to Yinxuhuowang syndrome, such as oral ulcers, and the imbalance in serum metabolites. And ZBDHD can improve oral cell inflammation and the imbalance of metabolism by inhibiting NF-κB and enhancing the activity of the ARE signalling pathway to ameliorate oxidative stress in the cell. This study provides a theoretical basis for the clinical application of ZBDHD.

Prostate cancer metastasis and soy isoflavones: a dogfight over a bone

Prostate cancer is a complex, progressive, bone-tropic disease, which is usually associated with skeletal issues, poor mobility and a fatal outcome when it reaches the metastatic phase. Soy isoflavones, steroid-like compounds from soy-based food/dietary supplements, have been found to decrease the risk of prostate cancer in frequent consumers. Herein, we present a systematization of the data on soy isoflavone effects at different stages of metastatic prostate cancer progression, with a particular interest in the context of bone-related molecular events. Specifically, soy isoflavones have been determined to downregulate the prostate cancer cell androgen receptors, reverse the epithelial to mesenchymal transition of these cells, decrease the expressions of prostate-specific antigen, matrix metalloproteinase and serine proteinase, and reduce the superficial membrane fluidity in prostate cancer cells. In addition, soy isoflavones suppress the angiogenesis that follows prostate cancer growth, obstruct prostate cancer cells adhesion to the vascular endothelium and their extravasation in the area of future bone lesions, improve the general bone morphofunctional status, have a beneficial effect on prostate cancer metastasis-caused osteolytic/osteoblastic lesions and possibly affect the pre-metastatic niche formation. The observed, multilevel antimetastatic properties of soy isoflavones imply that they should be considered as promising components of combined therapeutic approaches to advanced prostate cancer.