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The article highlights the results of a study on the prevalence and efficiency of treatment of osteoporosis in older men in Australia. According to the authors, 25 percent of older men met one or more of the Pharmaceutical Benefits Scheme (PBS) criteria while 90 percent of men who met the PBS criteria were not aware of having osteoporosis. They add that only small proportion of men had taken drugs to treat osteoporosis. The study illustrates the low level of awareness among men despite high incidence of osteoporosis in the country.

Objectives: In old age, there are marked changes in both the structure of the liver sinusoidal endothelial cell and liver perfusion. The objective of this study was to determine whether there are also aging changes in the microvascular architecture and vascular dispersion of the liver that might influence liver function. Methods: Vascular corrosion casts and light micrographs of young (4 months) and old (24 months) rat livers were compared. Fractal and Fourier analyses and micro-computed tomography were used. Vascular dispersion was determined from the dispersion number for sucrose and 100-nm microspheres in impulse response experiments. Results: Age did not affect sinusoidal dimensions, sinusoidal density, or dispersion number. There were changes in the geometry and complexity of the sinusoidal network as determined by fractal dimension and degree of anisotropy. Conclusions: There are small, age-related changes in the architecture of the liver sinusoidal network, which may influence hepatic function and reflect broader aging changes in the microcirculation. However, sinusoidal dimensions and hepatic vascular dispersion are not markedly influenced by old age. [ABSTRACT FROM AUTHOR]

The fenestrated sinusoidal endothelium (‘liver sieve’) and space of Disse in the healthy liver do not impede the transfer of most substrates, including drugs and oxygen, from the sinusoidal lumen to the hepatocyte. Plasma components transfer freely in both directions through the endothelial fenestrations and into the space of Disse. The endothelium is attenuated, there is no basement membrane and there is minimum collagen in the space of Disse, thus minimising any barriers to substrate diffusion. Both cirrhosis and aging are associated with marked structural changes in the sinusoidal endothelium and space of Disse that are likely to influence bulk plasma transfer into the space of Disse, and diffusion through the endothelium and space of Disse. These changes, termed capillarisation and pseudocapillarisation in cirrhosis and aging, respectively, impede the transfer of various substrates. Capillarisation is associated with exclusion of albumin, protein-bound drugs and macromolecules from the space of Disse, and the progressive transformation of flow-limited to barrier-limited distribution of some substrates. There is evidence that the sinusoidal changes in cirrhosis and aging contribute to hepatocyte hypoxia, thus providing a mechanism for the apparent differential reduction of oxygen-dependent phase I metabolic pathways in these conditions. Structural change and subsequent dysfunction of the liver sieve warrant consideration as a significant factor in the impairment of overall substrate handling and hepatic drug metabolism in cirrhosis and aging. [ABSTRACT FROM AUTHOR]

Cardiovascular disease secondary to atherosclerosis is the main cause of death and disability in industrialised countries, and ageing is the foremost risk factor for atherosclerosis. We present a hypothesis linking age-specific structural change in the liver with accepted pathogenic mechanisms leading to atherosclerosis. Ageing in the liver is associated with pseudocapillarisation of the sinusoidal endothelium, which is characterised by thickening of endothelium, basement membrane formation, and defenestration (loss of pores). Fenestrations (pores) normally form a liver sieve that allows passage of chylomicron remnants for subsequent uptake and metabolism by hepatocytes. Ageing is associated with impaired clearance of chylomicron remnants, postprandial hypertriglyceridaemia, and hence, atherosclerosis, which we propose is linked directly to loss of permeability of the liver sieve because of defenestration associated with pseudocapillarisation. Development of methods to maintain fenestrations of sinusoidal endothelium or to facilitate refenestration might be a new therapeutic strategy for management of cardiovascular disease in old people. [Copyright &y& Elsevier]

A correction is presented to the article, "The Effect of Aging on Acetaminophen Pharmacokinetics, Toxicity and Nrf2 in Fischer 344 Rats" which was published in a 2019 issue of the periodical.

Abstract: Age-related changes in the hepatic sinusoid of the rat, human and baboons called pseudocapillarization have been discovered and are important because they are considered to be implicated in the pathogenesis of some age-related diseases. In this study, we investigated whether similar changes occur in the livers of old mice. Livers of young (3–4 months) and old (20–24 months) mice were perfusion-fixed and studied using electron microscopy and immunohistochemistry. The thickness of the sinusoidal endothelium was increased in old mice (154±4 versus 244±8nm, P<0.001). There was a reduction in fenestrations within the endothelium (porosity decreased from 4.1±0.3 to 2.2±0.2%, P<0.001). There was perisinusoidal staining with Sirius red in old mice, however, expression of laminin and von Willebrands factor was similar in young and old mice. Novel perisinusoidal fat-engorged stellate cells were found extensively in the old mice. This study confirmed that pseudocapillarization is a widespread aging change in the liver, now documented in several species including the mouse. Mice are an appropriate animal model for studying aging and the hepatic sinusoid. [Copyright &y& Elsevier]

Rodents have been the primary model for mammalian nutritional physiology for decades. Despite an extensive body of literature, controversies remain around the effects of specific nutrients and total energy intake on several aspects of nutritional biology, even in this well-studied model. One approach that is helping to bring clarity to the field is the geometric framework for nutrition (GFN). The GFN is a multidimensional paradigm that can be used to conceptualize nutrition and nutritional effects, design experiments, and interpret results. To date, more than 30 publications have applied the GFN to data from rodent models of nutrition. Here we review the major conclusions from these studies. We pay particular attention to the effects of macronutrients on satiety, glucose metabolism, lifespan and the biology of aging, reproductive function, immune function, and the microbiome. We finish by highlighting several knowledge gaps that became evident upon reviewing this literature.