Endogenous Stem Cells in Homeostasis and Aging

In almost all human tissues and organs, adult stem cells or tissue stem cells are present in a unique location, the so-called stem cell niche or its equivalent, continuously replenishing functional differentiated cells. Those endogenous stem cells can be expanded for cell therapeutics using ex vivo cell culture or recalled for tissue repair in situ through cell trafficking and homing. In the aging process, inefficiency in the endogenous stem cell-mediated healing mechanism can emerge from a variety of impairments that accumulate in the processes of stem cell self-renewal, function, differentiation capacity, and trafficking through cell autonomous intrinsic pathways (such as epigenetic alterations) or systemic extrinsic pathways. This review examines the homeostasis of endogenous stem cells, particularly bone marrow stem cells, and their dysregulation in disease and aging and discusses possible intervention strategies. Several systemic pro-aging and rejuvenating factors, recognized in heterochronic parabiosis or premature aging progeroid animal models, are reviewed as possible anti-aging pharmaceutical targets from the perspective of a healthy environment for endogenous stem cells. A variety of epigenetic modifications and chromosome architectures are reviewed as an intrinsic cellular pathway for aging and senescence. A gradual increase in inflammatory burden during aging is also reviewed. Finally, the tissue repair and anti-aging effects of Substance-P, a peptide stimulating stem cell trafficking from the bone marrow and modifying the inflammatory response, are discussed as a future anti-aging target.

Parabiosis theory and effective stimulating amount, reinforcing-reducing, therapeutic time and course of acupuncture / 中国针灸

Parabiosis theory clearly expounds the change course of stimulatiom, namely, parabiotic equalization phase, parabiotic deregulation phase and parabiotic inhibition phase, and it can clearly explain that the effective stimulating amount is directly related to the reinforcing or reducing, and establishment of the therapeutic course. That is, the large effective stimulating amount is reducing method and the small effective stimulating amount is reinforcing method. In clinical application, for deficiency syndrome and chronic diseases, the effective intensity of acuti puncture should be smaller and the needle should be retained for 20-30 min, and for excess syndrome and acute disd eases, the effective stimulating intensity of acupuncture should be larger and the needle should be retained for longer time. In acupuncture treatment, acupoints should be grouped and used alternately, and the interval between therapeutic courses should be established.

The growth stimulating factor in parabiotic rats

Littermate Wistar rats were parabiosed at 30 days and daily individual food intake and individual weight gain of fifteen parabiotic pairs were recorded as control parabiotic pairs. Another fifteen pairs were used for the experiment in which one partner of parabiotic pair was completely fasted for 4 days and then refed ad libitum till body weight returned to the prefasting level and throughout the experiment, individual body weight changes and individual food intake of both partners of test parabiotic pairs were recorded. During fasting period, daily food intake and weight gain of non-fasted partner of test parabiotic pair increased significantly over that of the individual rat in control parabiotic pair. Moreover, weitht loss of fasted partner is same as that of individual fasted rat. The above findings indicated the presence of factor/factors in plasma of fasted partner stimulating food intake and growth of non-fasted partner of the test parabiotic pair. The present study also reveals that there is greater body weight increase per. g. food consumed (food conversion efficiency) of fasted partner during refeeding period whereas that of non-fasted partner decreased significantly during that period. Food intake and factors controlling it have been extensively studied by Physiologists and Nutritionists interested in growth and its regulation. Various extenal and endogenous stimuli initiate and terminate feeding. Of the endogenous stimuli humoral factors and their mode of action are the subjects of several recent studies (1,3,4,6). The present study is undertaken in order to further clarify and assess the role of humoral factor in the regulation of food intake and growth.

Teorias sobre a atuacao dos medicamentos homeopaticos / Theories about the actuation of the homeopathic drugs

Correlacionando teorias, discutiremos aspectos da Homeopatia no sentido de mostrar a importancia de dar-lhe uma base teorica cientificae, como os ensinamentos da neurofisiologia cortico-visceral de Pavlov podem lhe ser uteis, principalmente na explicacao do modo de acao dos medicamentos homeopaticos no organismo

Influence of stress on oxygen consumption and rectal temperature in parabiotic albino rats.

Stress can alter the functional status of the animal through a chain of complex interactions. In this work, influence of stress on oxygen consumption and rectal temperature was studied in parabiotic albino rats, to show the possibility of involvement of humoral factors. Stress has resulted in fall in rectal temperature and increase or decrease in oxygen consumption even when one animal of the pair was subjected to stress, suggesting involvement of humoral factor(s).