Low-protein/high-carbohydrate diet induces AMPK-dependent canonical and non-canonical thermogenesis in subcutaneous adipose tissue

Low-protein/high-carbohydrate (LPHC) diet has been suggested to promote metabolic health and longevity in adult humans and animal models. However, the complex molecular underpinnings of how LPHC diet leads to metabolic benefits remain elusive. Through a multi-layered approach, here we observed that LPHC diet promotes an energy-dissipating response consisting in the parallel recruitment of canonical and non-canonical (muscular) thermogenic systems in subcutaneous white adipose tissue (sWAT). In particular, we measured Ucp1 induction in association with up-regulation of actomyosin components and several Serca (Serca1, Serca2a, Serca2b) ATPases. In beige adipocytes, we observed that AMPK activation is responsible for transducing the amino acid lowering in an enhanced fat catabolism, which sustains both Ucp1-and Serca-dependent energy dissipation. Limiting AMPK activation counteracts the expression of brown fat and muscular genes, including Ucp1 and Serca, as well as mitochondrial oxidative genes. We observed that mitochondrial reactive oxygen species are the upstream molecules controlling AMPK-mediated metabolic rewiring in amino acid-restricted beige adipocytes. Our findings delineate a novel metabolic phenotype of responses to amino acid shortage, which recapitulates some of the benefits of cool temperature in sWAT. In conclusion, this highlights LPHC diet as a valuable and practicable strategy to prevent metabolic diseases through the enhancement of mitochondrial oxidative metabolism and the recruitment of different energy dissipating routes in beige adipocytes.

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LPHC diet promotes brown- and muscular-like features in sWAT.

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In vitro amino acid shortage mimics the effects of LPHC diet.

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AMPK controls canonical and non-canonical thermogenesis in sWAT.

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L-Cys replenishment limits the AMPK-mediated adaptive responses in sWAT.

Frataxin deficiency induces lipid accumulation and affects thermogenesis in brown adipose tissue

Decreased expression of mitochondrial frataxin (FXN) causes Friedreich's ataxia (FRDA), a neurodegenerative disease with type 2 diabetes (T2D) as severe comorbidity. Brown adipose tissue (BAT) is a mitochondria-enriched and anti-diabetic tissue that turns excess energy into heat to maintain metabolic homeostasis. Here we report that the FXN knock-in/knock-out (KIKO) mouse shows hyperlipidemia, reduced energy expenditure and insulin sensitivity, and elevated plasma leptin, recapitulating T2D-like signatures. FXN deficiency leads to disrupted mitochondrial ultrastructure and oxygen consumption as well as lipid accumulation in BAT. Transcriptomic data highlights cold intolerance in association with iron-mediated cell death (ferroptosis). Impaired PKA-mediated lipolysis and expression of genes controlling mitochondrial metabolism, lipid catabolism and adipogenesis were observed in BAT of KIKO mice as well as in FXN-deficient T37i brown and primary adipocytes. Significant susceptibility to ferroptosis was observed in adipocyte precursors that showed increased lipid peroxidation and decreased glutathione peroxidase 4. Collectively our data point to BAT dysfunction in FRDA and suggest BAT as promising therapeutic target to overcome T2D in FRDA.

C-reactive protein in viral and bacterial gastroenteritis in childhood

To differentiate bacterial from viral infections the level of C-reactive protein in serum samples was studied in three groups of children under 5 years of age with gastroenteritis. Of the 53 children with bacterial infection, 41 (77%) had C-reactive protein levels > or = 12 mg1 -1, 32 (66%) > or = 20 mgl-1 and 24 (45%) > or = 35 mgl-1. Of the 35 patients with viral infection, 4 (11%) had C-reactive protein levels > or = 12 mgl-1, 3 (9%) > or = 20 mgl-1 and 1 (3%) > or = 35 mgl-1. The best balance between sensitivity and specificity of C-reactive protein was obtained for a cut-off level > or = 12 mgl-1 (sensitivity 77%, specificity 89%) as compared to > or = 20 mgl-1 (sensitivity 58%, specificity 97%) and > or = 35 mgl-1 (sensitivity 44%, specificity 97%). Our results suggest that the determination of C-reactive protein values may be a useful tool for predicting bacterial gastroenteritis in children.

[Cholelithiasis in children: observations on a further case and the technique of laparoscopic cholecystectomy in a child]

A new case of gallstone in a child, with non apparent predisposing condition, who underwent laparoscopic cholecystectomy is reported. The importance of considering cholelithiasis in children with abdominal pain as well as the value of ultrasonography in diagnosis is stressed. The technique of laparoscopic cholecystectomy modified for pediatric patients and its benefits (decreased pain and ileus after surgery, shortened hospitalization and improved cosmesis) are discussed.

[Aplasia cutis congenita: report of 4 additional cases and review of the literature]

Aplasia cutis congenita is a heterogeneous group of disorders characterized by focal absence of skin at birth. In the majority of cases, the involved area is limited to the scalp. These disorders are relatively rare. As a result of misinterpretation, medicolegal advice can be sought by parents who believed that their child's scalp had been injured during surgical induction of labour or fetal monitoring. We report four additional patients (two familiar and two sporadic cases) and discuss, in the light of a comprehensive review of the literature, the probable pathogenesis, the clinical variability and the treatment.

[Clinico-epidemiological observations of 77 pediatric cases of infection with non-typhi salmonellae]

Non-typhoid salmonellosis remains a common infective illness. We studied 77 consecutively admitted children aged 1 month to 15 years in order to determine frequency of antecedents, the strain of the isolated organisms, clinical findings, frequency of complications and the adequacy of management. The presentation and severity of the illness were compared between younger than two and older children. Salmonella typhimurium was isolated in 65% of the cases. Two thirds of the tested strains were multiresistant to antibiotics. Non-typhoid salmonellosis usually occurred in the form of acute gastroenteritis: in only 4% of the cases it presented as pyrexia of unknown origin without gastrointestinal symptoms. 30% of the cases had been exposed to one or more antimicrobial agents within four weeks before the date of their stool culture. Only 30% had been breast fed. Previously diagnosed cow's milk protein intolerance resulted to be present in 14% of the less than two years old children (p < 0.02). Abdominal pain and headache were found more frequently in older children (p < 0.02). Protein C reactive values were significantly higher in this age group (p < 0.05). 25% of the children were mildly or moderately dehydrated. Hypernatremia was uncommon. 31% of the cases were treated with antibiotics: the antimicrobial treated children presented diarrhoea for longer period (p < 0.05) and they remained admitted for longer time (p < 0.00).(ABSTRACT TRUNCATED AT 250 WORDS)

[Spontaneous pneumomediastinum in an adolescent]

Spontaneous pneumomediastinum is defined as nontraumatic mediastinal air leak in patients without underlying lung disease. In children and adolescents it is rarely described and is likely to be underdiagnosed. We describe a case. The aetiopathogenesis, clinical findings, diagnosis and treatment are discussed.

A two-year survey of mucocutaneous lymph node syndrome in northeastern Italy. Epidemiological and clinical findings

A two-year retrospective survey of cases of mucocutaneous lymph node syndrome (MLNS, Kawasaki disease) was conducted by a collaborative research group in Northeastern Italy (Friuli Venezia-Giulia) by reviewing the records of all patients admitted in the paediatric wards of this area from January 1, 1981 to December 31, 1982. 19 cases of MLNS were identified representing an overall incidence in the two-year period of 14.7 cases per 100,000 children younger than 5 years of age. Seasonal clustering of cases was observed, 17 out of 19 cases occurring either in spring or autumn (P = 0.0004, binomial distribution) and 11 out of 19 cases occurring in spring alone (P = 0.0023). No evidence for direct contact between cases or common source exposure emerged, and no risk factors were identified. The clinical spectrum of the disease was similar to that described elsewhere, carditis, uveitis, arthritis and urethritis being the most frequent complications. One infant died, and in this case coronary artery aneurysms were demonstrated by two-dimensional echocardiography. In the remaining cases recovery was complete without sequelae. This study suggests that MLNS is more frequent than expected and that the real incidence of the disease is probably underestimated. The evidence of seasonal clustering of cases strongly suggests the presence of a yet unidentified exogenous factor playing a role in the etiology of the disease.