Type 1 collagen marker of bone turnover, insulin-like growth factor, and leptin in dichorionic twins with discordant birth weight

Blockade of Macrophage CD147 Protects Against Foam Cell Formation in Atherosclerosis

The persistence of macrophage-derived foam cells in the artery wall fuels atherosclerosis development. However, the mechanism of foam cell formation regulation remains elusive. We are committed to determining the role that CD147 might play in macrophage foam cell formation during atherosclerosis. In this study, we found that CD147 expression was primarily increased in mouse and human atherosclerotic lesions that were rich in macrophages and could be upregulated by ox-LDL. High-throughput compound screening indicated that ox-LDL-induced CD147 upregulation in macrophages was achieved through PI3K/Akt/mTOR signaling. Genetic deletion of macrophage CD147 protected against foam cell formation by impeding cholesterol uptake, probably through the scavenger receptor CD36. The opposite effect was observed in primary macrophages isolated from macrophage-specific CD147-overexpressing mice. Moreover, bioinformatics results indicated that CD147 suppression might exert an atheroprotective effect via various processes, such as cholesterol biosynthetic and metabolic processes, LDL and plasma lipoprotein clearance, and decreased platelet aggregation and collagen degradation. Our findings identify CD147 as a potential target for prevention and treatment of atherosclerosis in the future.

Placental Growth Factor and Endothelial Cell-Specific Molecule 1 Levels in Discordant and Concordant Twins and Their Effects on Fetal Growth

OBJECTIVE

We explored whether fetal twin growth was related to the levels of placental growth factor (PGF) and endothelial cell-specific molecule 1 (ESM-1) and sought correlations between cord blood PGF and ESM1 levels and birth weight discordance.

METHODS

This was a prospective study. We evaluated 79 pairs of twins, thus 158 infants. Twenty-nine (37%) twins were naturally conceived; the remaining 50 (63%) resulted from assisted reproduction.

RESULTS

Nine (11%) sets of twins were monochorionic. Eighteen of the 79 twin sets (22%) were discordant. We found a positive correlation between PGF and ESM-1 levels (r = 0.51, p = 0.001) and between discordance and PGF level (r = 0.430, p = 0.001).

CONCLUSION

The growth discordance may not be attributable to the different PGF levels, but the difference in PGF level may be a consequence.

Leptin and adiponectin levels in discordant dichorionic twins at 72 hours of age-associations with anthropometric parameters and insulin resistance

BACKGROUND

Insulin resistance (IR) in adults has been associated with intrauterine growth restriction (IUGR). Leptin and adiponectin correlations with anthropometric parameters and IR at 72 h in discordant twins were tested.

METHODS

We included 24 discordant (birth weight discordance ≥20% in relation to the heavier cotwin) and 30 concordant (birth weight discordance ≤10%) twins.

RESULTS

A correlation between leptin (but not adiponectin) level and birth weight (BW), birth length and head circumference in IUGR twins was recorded (p<0.05). Insulin sensitivity (IS) and homeostatic model assessment (HOMA)-IR in IUGR twins were similar to appropriate-for-gestational-age cotwins and unrelated to adipokines. In IUGR twins, adiponectin and insulin associated positively. In larger concordant twins' leptin level correlated with HOMA-IR and insulin.

CONCLUSIONS

Leptin, but not adiponectin, levels correlate positively with anthropometric parameters in IUGR twins. IR in IUGR twins is unrelated to adipokines in the first few days of life.

Leptin and adiponectin levels in discordant dichorionic twins at 72 hours of age-associations with anthropometric parameters and insulin resistance

Background:

Insulin resistance (IR) in adults has been associated with intrauterine growth restriction (IUGR). Leptin and adiponectin correlations with anthropometric parameters and IR at 72 h in discordant twins were tested.

Methods:

We included 24 discordant (birth weight discordance ≥20% in relation to the heavier cotwin) and 30 concordant (birth weight discordance ≤10%) twins.

Results:

A correlation between leptin (but not adiponectin) level and birth weight (BW), birth length and head circumference in IUGR twins was recorded (p<0.05). Insulin sensitivity (IS) and homeostatic model assessment (HOMA)-IR in IUGR twins were similar to appropriate-for-gestational-age cotwins and unrelated to adipokines. In IUGR twins, adiponectin and insulin associated positively. In larger concordant twins’ leptin level correlated with HOMA-IR and insulin.

Conclusions:

Leptin, but not adiponectin, levels correlate positively with anthropometric parameters in IUGR twins. IR in IUGR twins is unrelated to adipokines in the first few days of life.

Prospective study of histomorphometry, biochemical bone markers and bone densitometric response to pamidronate in β-thalassaemia presenting with osteopenia-osteoporosis syndrome

This study aimed to evaluate bone remodelling disorders in thalassaemia by using pamidronate (PD) infusion with or without hormone replacement therapy (HRT) as a diagnostic-therapeutic tool. In this prospective study, 24 adult thalassaemia major (TM) and 10 thalassaemia intermedia (TI) patients received either PD and HRT or HRT only (controls) for 3 years. Eugonadal patients with TI had PD only. Bone remodelling was assessed by dual energy X ray absorptiometry (DXA scan), type 1-collagen biochemical bone markers (BBM) and histomorphometry of iliac crest biopsy before and after PD. As a group, thalassaemics had a significant improvement in spinal and femoral bone mineral density Z scores following PD (P < 0·01) compared to the controls. Although BBM were comparable pre-therapy, they were significantly lower in the PD cohort (P < 0·001) compared to the control group. All patients had osteopenia, diminished osteoid formation and bone volume on histomorphometry pre-therapy with high turnover bone disease (HTO) in TM and low-turnover disease (LTO) in TI. In TM, bone volume improved significantly, whereas TI patients showed little or no response to PD. In conclusion, histomorphometry data suggest that TM patients have a distinct pathology of high turnover bone disease compared to TI patients, who have low-turnover disease.

Use of hormone replacement therapy for correction of high turnover bone disease in hypogonadal β-Thalassemia major patients presenting with osteoporosis: comparison with idiopathic premature ovarian failure

Osteopenia-osteoporosis syndrome (OOS) causes considerable morbidity in 60-80% β-thalassemia major (β-TM) patients. We evaluated the effect of sex hormone replacement therapy (HRT) in β-TM patients with hypogonadism presenting with OOS using premature ovarian failure (POF) for comparative purposes. We undertook a 10-year prospective study of in 50 β-TM and 375 patients with POF and OOS. All were treated with HRT for 2-5 years. We used dual X-ray absorptiometry (DEXA), and plasma type 1-collagen markers of bone turnover for monitoring of response to therapy. Our results suggest that prior to HRT, both groups had comparable degrees of OOS. Both groups had significant improvement but the POF group had normalization of spinal T scores following HRT in contrast to the β-TM patients. Femoral T scores did not normalize in both groups. These data indicate for the first time from comparative POF control studies that hypogonadism is not the only cause of OOS in β-TM.

Insulin-like growth factor-1 levels in twins and its correlation with discordance

This study aims to determine whether fetal growth is related to insulin-like growth factor-1 in dichorionic and monochorionic twins and also aims to investigate the correlation of insulin-like growth factor-1 to birthweight discordance in twins. We studied 100 women with twin pregnancies. The correlation tests of 36 discordant twins (15 monochorionic, 21 dichorionic) showed correlation between insulin-like growth factor-1 difference and birthweight discordance (insulin-like growth factor-1 vs. birthweight of first twin, r = +0.915, at 0.01 level, IGF-1 vs birthweight of second twin r = +0.790, at 0.01 level). In 49 monochorionic twins, independent of discordance, there was a correlation between birthweight discordance and insulin-like growth factor-1 difference (r = .538, at the 0.01 level). This correlation was not significant in dichorionic twins, r = .144, p = .01. These data suggest that growth discordances of twins exposed to the same maternal environment may be due to variations in IGF-1, depending upon the genetic similarity.

Perinatal bone turnover in term pregnancies: the influence of intrauterine growth restriction

Intrauterine growth restriction (IUGR) has been associated with low bone mass in infancy and increased risk for osteoporosis development in adult life. We aimed to investigate the effect of IUGR on bone metabolism in mother/infant pairs, by determining circulating biochemical markers of bone turnover in IUGR and appropriate for gestational age (AGA) pregnancies. Circulating markers of bone formation [bone specific alkaline phosphatase (BALP), total alkaline phosphatase (ALP), osteocalcin (OC)] and bone resorption [cross-linked N-telopeptide of type I collagen (NTx)], as well as intact parathormone (PTH), calcium and phosphorus levels were measured in 40 mothers and their 20 IUGR and 20 AGA singleton full-term fetuses and neonates on postnatal days 1 (N1) and 4 (N4). No significant differences in BALP, ALP, OC, NTx, PTH, calcium or phosphorus levels were observed between the AGA and the IUGR groups. In both groups, maternal BALP levels were lower compared to fetal, N1 and N4 levels (p< or =0.005 in all cases). In the AGA group, maternal NTx and OC levels were lower compared to fetal, N1 and N4 levels (p<0.001 in all cases), and fetal NTx levels were lower compared to N1 and N4 ones (p<0.001 and p=0.002, respectively). In the IUGR group, maternal OC levels were lower compared to fetal, N1 and N4 ones (p<0.001 in each case) and fetal OC levels were elevated compared to N1 and N4 ones (p<0.001 and p=0.003, respectively). N4 NTx levels were elevated compared to maternal, fetal and N1 levels (p=0.009, p<0.001 and p=0.002, respectively) and fetal NTx levels were lower compared to N1 and N4 ones (p=0.001 and p<0.001, respectively). Finally, positive correlations were found between maternal NTx and BALP (r=0.332, p=0.037), as well as ALP (r=0.329, p=0.038) levels, and between maternal, fetal, N1, N4 BALP and respective ALP levels (r=0.432, p=0.005, r=0.534, p=0.001, r=0.778, p<0.001, r=0.694, p<0.001, respectively). In conclusion, maternal, fetal and neonatal bone turnover in IUGR cases may not differ from respective bone metabolism in AGA controls. In addition, fetal and neonatal bone remodeling is markedly enhanced and independent of maternal bone turnover in late pregnancy.

Opposite effects of leptin on bone metabolism: a dose-dependent balance related to energy intake and insulin-like growth factor-I pathway

Published data describing leptin effects on bone are at variance with both positive and negative consequences reported. These findings are consistent with a bimodal threshold response to serum leptin levels. To test this theory, two groups of female rats (tail-suspended and unsuspended) were treated with ip leptin at two different doses or vehicle for 14 d. In tail-suspended rats, low-dose leptin compensated the decrease in serum leptin levels observed with suspension and was able to prevent the induced bone loss at both the trabecular and cortical level (assessed by three-dimensional microtomography). In contrast, high-dose leptin inhibited femoral bone growth and reduced bone mass by decreasing bone formation rate and increasing bone resorption in both tail-suspended and unsuspended groups. High- and low-dose leptin administration resulted in a reduced medullar adipocytic volume in all groups. High-dose leptin (but not low) induced a decrease in body-weight abdominal fat mass and serum IGF-I levels. Thus, the observed bone changes at high-dose leptin are at least partly mediated by a leptin-induced energy imbalance. In conclusion, a balance between negative and positive leptin effects on bone is dependent on a bimodal threshold that is triggered by leptin serum concentration. Also, the negative effects of high leptin levels are likely induced by reduced energy intake and related hormonal changes. The respective part of each pathway will be unraveled by additional studies.