The proteasome inhibitor bortezomib may increase osteoblast-related markers in multiple myeloma (MM) patients; however, its potential osteoblastic stimulatory effect is not known. In this study, we show that bortezomib significantly induced a stimulatory effect on osteoblast markers in human mesenchymal cells without affecting the number of osteoblast progenitors in bone marrow cultures or the viability of mature osteoblasts. Consistently we found that bortezomib significantly increased the transcription factor Runx2/Cbfa1 activity in human osteoblast progenitors and osteoblasts without affecting nuclear and cytoplasmatic active β-catenin levels. Consequently a stimulatory effect of bortezomib on bone nodule formation was also demonstrated in osteoblast progenitors. These in vitro observations were confirmed in vivo by the finding of a significant increase in the number of osteoblastic cells × mm2 of bone tissue and in the number of Runx2/Cbfa1-positive osteoblastic cells that was observed in MM patients who responded to bortezomib. Our in vitro and in vivo observations support the hypothesis that a direct stimulatory effect on bone formation process could occur during bortezomib treatment.

Oropharyngeal dysphagia (OD) is a widespread clinical condition among older adults. Although it represents a risk factor for malnutrition, dehydration and aspiration pneumonia, its assessment and contribution to functional decline is often ignored. The aim of the present study was to estimate the prevalence of OD in a large population of non-institutionalized older people and to evaluate its relationship with malnutrition and physical function. 10-item Eating Assessment Tool (EAT-10) and Mini Nutritional Assessment Short Form (MNA-SF) were used to identify the risk of dysphagia and malnutrition. Short Physical Performance Battery (SPPB) and hand-grip strength were used as functional endpoints. The relationship between risk of dysphagia and functional outcomes was tested in a multivariate regression analysis adjusted for age and sex (Model 1) and for other confounders including Mini Mental State Examination (MMSE) and polypharmacy (Model 2). Mean age of 773 subjects (61.3% female) was 81.97 years. The percentage of participants at risk of dysphagia (EAT ≥ 3) was 30.1%, 37.8% of subjects was malnourished (MNA-SF < 8), 46.2% was at risk of malnutrition (MNA-SF:8-11). EAT-10 was significantly and negatively associated to MNA-SF (β = -0.47 ± 0.06, p < 0.0001) and the strength of the relationship was attenuated but still statistically significant in the multivariate model (β = -0.28 ± 0.07, p < 0.0001). A significant and negative relationship was found between EAT-10 and SPPB and hand-grip strength in Model 1 (β = -0.25 ± 0.05, p < 0.0001) and Model 2 (β = -0.07 ± 0.03, p < 0.0001). After categorization of risk of dysphagia in two groups (at risk and not at risk), MNA-SF, SPPB and hand-grip strength were independently associated with higher risk of dysphagia (OR = 0.91, 95%CI = 0.83-0.99, p = 0.03; OR = 0.83, 95%CI = 0.77-0.89, p < 0.0001; OR = 0.96, 95%CI = 0.92-0.99, p = 0.02, respectively). In a large group of outpatient older individuals, we observed a significant negative association between risk of dysphagia and nutritional and physical performance, suggesting that the screening of OD, possibly supported by its assessment, should be implemented in the geriatric setting to potentially prevent the functional decline.

The gut microbiota could influence the pathophysiology of age-related sarcopenia through multiple mechanisms implying modulation of chronic inflammation and anabolic resistance. The aim of this study was to compare the fecal microbiota composition and functionality, assessed by shotgun metagenomics sequencing, between two groups of elderly outpatients, differing only for the presence of primary sarcopenia. Five sarcopenic elderly subjects and twelve non-sarcopenic controls, classified according to lower limb function and bioimpedance-derived skeletal muscle index, provided a stool sample, which was analyzed with shotgun metagenomics approaches, to determine the overall microbiota composition, the representation of bacteria at the species level, and the prediction of bacterial genes involved in functional metabolic pathways. Sarcopenic subjects displayed different fecal microbiota compositions at the species level, with significant depletion of two species known for their metabolic capacity of producing short-chain fatty acids (SCFAs), Faecalibacterium prausnitzii and Roseburia inulinivorans, and of Alistipes shahii. Additionally, their fecal metagenome had different representation of genes belonging to 108 metabolic pathways, namely, depletion of genes involved in SCFA synthesis, carotenoid and isoflavone biotransformation, and amino acid interconversion. These results support the hypothesis of an association between microbiota and sarcopenia, indicating novel possible mediators, whose clinical relevance should be investigated in future studies.

Angiogenesis has a critical role in the pathophysiology of multiple myeloma (MM); however, the molecular mechanisms underlying this process are not completely elucidated. The new tumor-suppressor gene inhibitor of growth family member 4 (ING4) has been recently implicated in solid tumors as a repressor of angiogenesis. In this study, we found that ING4 expression in MM cells was correlated with the expression of the proangiogenic molecules interleukin-8 (IL-8) and osteopontin (OPN). Moreover, we demonstrate that ING4 suppression in MM cells up-regulated IL-8 and OPN, increasing the hypoxia inducible factor-1α (HIF-1α) activity and its target gene NIP-3 expression in hypoxic condition. In turn, we show that the inhibition of HIF-1α by siRNA suppressed IL-8 and OPN production by MM cells under hypoxia. A direct interaction between ING4 and the HIF prolyl hydroxylase 2 (HPH-2) was also demonstrated. Finally, we show that ING4 suppression in MM cells significantly increased vessel formation in vitro, blunted by blocking IL-8 or OPN. These in vitro observations were confirmed in vivo by finding that MM patients with high IL-8 production and microvascular density (MVD) have significantly lower ING4 levels compared with those with low IL-8 and MVD. Our data indicate that ING4 exerts an inhibitory effect on the production of proangiogenic molecules and consequently on MM-induced angiogenesis.