Cellular Turnover: A Potential Metabolic Rate–Driven Mechanism to Mitigate Accumulation of DNA Damage

Ionizing radiation (IR) is one of the conventional post-surgical treatments for Glioblastoma Multiforme (GBM). Mesenchymal stem cells (MSCs) constitute a subpopulation of bone marrow derived cells which are actively recruited to the site of radiation and/or tumour microenvironment (TME), both of which have important implications for neovascularization and tumor progression. The goal of this project is to investigate the functional contribution of MSCs in the TME. We postulate that Bone Marrow-MSCs promote radio-resistance in GBM via cell cycle arrest. We tested the effect of MSC on U87 glioblastoma cell line in response to IR. We found that MSC co-culture, MSC-conditioned media (MSCCM) and irradiated MSC-conditioned media (MSCIRCM) did not reduce IR-induced p53 (ser15) phosphorylation, signifying intact p53-dependent DNA damage pathway in all conditions. However, both MSCCM and MSCIRCM temporally increased phospho-Chk2, a kinase involved in ATM-dependent cascade and cell cycle arrest. This increase occurred at 24 hours and reverted to baseline levels by 48 hours. Interestingly, IR (15Gy) caused transiently heightened metabolic rate under MSC and MSC IRCM as opposed to IR-null treatment at 48 hours elevated cell proliferation. MSCCM, but not MSCIRCM, marginally reduced caspase 3/7-dependent apoptotic levels. The combination of IR and MSCCM as well as MSCIRCM first increased protein level of phospho-Chk2 at 24 hours; followed by increased metabolic rate at 48 hours; and lastly, boosted proliferation at 72 hours. This data combined proposes plausible machinery for BM-MSC mediated radio-resistance by initiating cell cycle arrest in tumour cells for DNA damage repair.

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1576: Prediction of Spermatozoal DNA Damage by a Novel Semen Quality Score

The Journal of Urology ◽

10.1016/s0022-5347(18)38784-6 ◽

2004 ◽

Vol 171 (4S) ◽

pp. 416-416

Author(s):

Tamer M. Said ◽

Shyam Allamaneni ◽

Kiran P. Nallella ◽

Rakesh K. Sharma ◽

Sijo J. Parekattil ◽

...

Keyword(s):

Dna Damage ◽

Semen Quality ◽

Quality Score

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Development of new predictive equations for basal metabolic rate in Iranian healthy adults: negligible effect of sex

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000669 ◽

2020 ◽

pp. 1-10

Author(s):

Bahareh Nikooyeh ◽

Nastaran Shariatzadeh ◽

Ali Kalayi ◽

Maliheh Zahedirad ◽

Tirang R. Neyestani

Keyword(s):

Metabolic Rate ◽

Thyroid Function ◽

Basal Metabolic Rate ◽

Age Groups ◽

Thyroid Function Tests ◽

Anthropometric Measures ◽

Predictive Equations ◽

Normal Thyroid Function ◽

Asian People ◽

Predictive Formulas

Abstract. Some studies have reported inaccuracy of predicting basal metabolic rate (BMR) by using common equations for Asian people. Thus, this study was undertaken to develop new predictive equations for the Iranian community and also to compare their accuracy with the commonly used formulas. Anthropometric measures and thyroid function were evaluated for 267 healthy subjects (18–60 y). Indirect calorimetry (InCal) was performed only for those participants with normal thyroid function tests (n = 252). Comparison of predicted RMR (both kcal/d and kcal.kg.wt−1.d−1) using current predictive formulas and measured RMR revealed that Harris-Benedict and FAO/WHO/UNU significantly over-estimated and Mifflin-St. Jeor significantly under-estimated RMR as compared to InCal measurements. In stepwise regression analysis for developing new equations, the highest r2 (=0.89) was from a model comprising sex, height and weight. However, further analyses revealed that unlike the subjects under 30 y, the association between age and the measured RMR in subjects 30 y and plus was negative (r = −0.241, p = 0.001). As a result, two separate equations were developed for these two age groups. Over 80 percent of variations were covered by the new equations. In conclusion, there were statistical significant under- and over-estimation of RMR using common predictive equations in our subjects. Using the new equations, the accuracy of the calculated RMR increased remarkably.

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Nutrient pattern of unsaturated fatty acids and vitamin E increase resting metabolic rate of overweight and obese women

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000664 ◽

2020 ◽

pp. 1-9

Author(s):

Habib Yarizadeh ◽

Leila Setayesh ◽

Caroline Roberts ◽

Mir Saeed Yekaninejad ◽

Khadijeh Mirzaei

Keyword(s):

Vitamin E ◽

Metabolic Rate ◽

Unsaturated Fatty Acids ◽

Resting Metabolic Rate ◽

Blood Parameters ◽

Cross Sectional Study ◽

Obese Women ◽

Cross Sectional ◽

Dietary Nutrients ◽

Nutrient Patterns

Abstract. Objectives: Obesity plays an important role in the development of chronic diseases including cardiovascular disease and diabetes. A low resting metabolic rate (RMR) for a given body size and composition is a risk factor for obesity, however, there is limited evidence available regarding the association of nutrient patterns and RMR. The aim of this study was to determine the association of nutrient patterns and RMR in overweight and obese women. Study design: This cross-sectional study was conducted on 360 women who were overweight or obese. Method: Dietary intake was assessed using a semi-quantitative standard food frequency questionnaire (FFQ). Nutrient patterns were also extracted by principal components analysis (PCA). All participants were evaluated for their body composition, RMR, and blood parameters. Result: Three nutrient patterns explaining 64% of the variance in dietary nutrients consumption were identified as B-complex-mineral, antioxidant, and unsaturated fatty acid and vitamin E (USFA-vit E) respectively. Participants were categorized into two groups based on the nutrient patterns. High scores of USFA-vit E pattern was significantly associated with the increase of RMR (β = 0.13, 95% CI = 0.79 to 68.16, p = 0.04). No significant associations were found among B-complex-mineral pattern (β = −0.00, 95% CI = −49.67 to 46.03, p = 0.94) and antioxidant pattern (β = 0.03, 95% CI −41.42 to 22.59, p = 0.56) with RMR. Conclusion: Our results suggested that the “USFA-vit E” pattern (such as PUFA, oleic, linoleic, vit.E, α-tocopherol and EPA) was associated with increased RMR.

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