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Background: Alzheimer’s disease (AD) has minimally effective treatments currently. High concentrations of resveratrol, a polyphenol antioxidant found in plants, have been reported to affect several AD-related and neuroprotective genes. To address the low bioavailability of resveratrol, we investigated a novel oral formulation of resveratrol, JOTROL™, that has shown increased pharmacokinetic properties compared to non-formulated resveratrol in animals and in humans. Objective: We hypothesized that equivalent doses of JOTROL, compared to non-formulated resveratrol, would result in greater brain exposure to resveratrol, and more efficacious responses on AD biomarkers. Methods: For sub-chronic reversal studies, 15-month-old male triple transgenic (APPSW/PS1M146V/TauP301L; 3xTg-AD) AD mice were treated orally with vehicle or 50 mg/kg JOTROL for 36 days. For prophylactic studies, male and female 3xTg-AD mice were similarly administered vehicle, 50 mg/kg JOTROL, or 50 mg/kg resveratrol for 9 months starting at 4 months of age. A behavioral battery was run, and mRNA and protein from brain and blood were analyzed for changes in AD-related gene and protein expression. Results: JOTROL displays significantly increased bioavailability over non-formulated resveratrol. Treatment with JOTROL resulted in AD-related gene expression changes (Adam10, Bace1, Bdnf, Psen1) some of which were brain region-dependent and sex-specific, as well as changes in inflammatory gene and cytokine levels. Conclusion: JOTROL may be effective as a prophylaxis and/or treatment for AD through increased expression and/or activation of neuroprotective genes, suppression of pro-inflammatory genes, and regulation of central and peripheral cytokine levels.

Alzheimer's disease (AD) has minimally effective treatments currently. High concentrations of resveratrol, a polyphenol antioxidant found in plants, have been reported to affect several AD-related and neuroprotective genes. To address the low bioavailability of resveratrol, we investigated a novel oral formulation of resveratrol, JOTROL™, that has shown increased pharmacokinetic properties compared to non-formulated resveratrol in animals and in humans.We hypothesized that equivalent doses of JOTROL, compared to non-formulated resveratrol, would result in greater brain exposure to resveratrol, and more efficacious responses on AD biomarkers.For sub-chronic reversal studies, 15-month-old male triple transgenic (APPSW/PS1M146V/TauP301L; 3xTg-AD) AD mice were treated orally with vehicle or 50 mg/kg JOTROL for 36 days. For prophylactic studies, male and female 3xTg-AD mice were similarly administered vehicle, 50 mg/kg JOTROL, or 50 mg/kg resveratrol for 9 months starting at 4 months of age. A behavioral battery was run, and mRNA and protein from brain and blood were analyzed for changes in AD-related gene and protein expression.JOTROL displays significantly increased bioavailability over non-formulated resveratrol. Treatment with JOTROL resulted in AD-related gene expression changes (Adam10, Bace1, Bdnf, Psen1) some of which were brain region-dependent and sex-specific, as well as changes in inflammatory gene and cytokine levels.JOTROL may be effective as a prophylaxis and/or treatment for AD through increased expression and/or activation of neuroprotective genes, suppression of pro-inflammatory genes, and regulation of central and peripheral cytokine levels.

Administration of estradiol 17 beta [estra-1,3,5(10)-triene-3,17-beta-diol] to male Xenopus laevis induces the massive synthesis by the liver of the egg yolk precursor phospholipoglycoprotein, vitellogenin, and its cognate mRNAs. Restimulation of male X. laevis that have been previously induced to synthesize vitellogenin mRNA but are inactive in vitellogenin mRNA synthesis at the time of restimulation with estrogen results in more rapid accumulation of vitellogenin mRNA and more efficient transcription of the vitellogenin genes than occurs following primary estrogen stimulation. The estrogen receptor system that mediates estrogen action in this organism exhibits several unusual properties. The cytoplasm of unstimulated liver cells contains high levels of a middle-affinity estrogen-specific binding protein and little if any estrogen receptor. The properties of the estrogen binding protein are consistent with a role in protecting estradiol 17 beta against metabolism, as a fraction of cytoplasmic estradiol 17 beta is not subject to rapid metabolism. In addition, similar binding activities are found in all Xenopus tissues surveyed that respond to steroid hormones. The induction of nuclear estrogen receptor is coincident with the onset of vitellogenin mRNA accumulation. However, an increased level of estrogen receptor is not responsible for the elevated rate of vitellogenin gene transcription observed following restimulation with estrogen.

Estrogen induces the synthesis of vitellogenin mRNA by activating transcription of the vitellogenin genes. Quantitative inhibition of liver protein synthesis by cycloheximide does not prevent activation of vitellogenin gene transcription. The relative transcription rate of the vitellogenin genes in estrogen stimulated liver is similar in control and cycloheximide treated animals (800-1000 ppm). Selective estrogen activation of vitellogenin gene transcription therefore represents a direct effect of estrogen on vitellogenin gene transcription which can occur without any change in the cells' protein complement. Two other cellular responses to estrogen, the induction of nuclear estrogen receptor, and an increased rate of total nuclear RNA synthesis, are blocked by cycloheximide administration. Since the overall rate of vitellogenin mRNA synthesis is a function of both the selective estrogen activation of vitellogenin gene transcription which is not blocked by cycloheximide and the increased rate of total nuclear RNA synthesis which is blocked by cycloheximide, the total rate of vitellogenin mRNA synthesis is markedly reduced following cycloheximide administration.

We have used plus-minus hybridization to identify Xenopus liver cDNA clones of mRNAs whose levels are regulated by estrogen. One clone identified in this way was shown to be a nearly full-length cDNA clone of the mRNA coding for a small 22 000 dalton estrogen-inducible serum protein (EISP). Quantitation of EISP mRNA levels by in vitro translation and by hybridization to the cloned DNA demonstrated a 7–12-fold estrogen induction of EISP mRNA, both in vivo and in primary Xenopus liver cultures. The kinetics of induction of EISP mRNA closely parallel those of the mRNA coding for the abundant estrogen-inducible serum protein, vitellogenin. In contrast, the massive, and toxic, estrogen-mediated accumulation of vitellogenin in serum of male Xenopus laevis is accompanied by a sharp decline in the levels of albumin mRNA and in the levels of the mRNAs coding for several other serum proteins.

Estrogen activates transcription of the vitellogenin genes in livers of male Xenopus laevis. We have examined the conformation of the vitellogenin genes in chromatin and the methylation state of one vitellogenin gene during the process of estrogen stimulation and withdrawal. Sensitivity of the vitellogenin genes to DNase I digestion parallels transcription. The vitellogenin genes are insensitive to DNase I digestion in unstimulated liver cells, become more sensitive to DNase I digestion following estrogen activation of vitellogenin gene transcription, and are insensitive to DNase I digestion in liver cells withdrawn from estrogen. In contrast, the methylation state of nine potential methylation sites within the vitellogenin A1 gene is identical in red blood cells, unstimulated and withdrawn liver, estrogen-stimulated liver, and hepatocytes purified from estrogen-stimulated liver. Rapid transcription of the vitellogenin genes in estrogen-stimulated liver cells occurs with six of the nine methylation sites examined fully methylated.

The levels of cytoplasmic and nuclear estrogen receptor have been determined in livers of male Xenopus laevis stimulated by estradiol-17 beta to synthesize vitellogenin mRNA. Estrogen receptor levels were also determined in unstimulated liver and following long term withdrawal of estrogen. In unstimulated liver cells, which do not contain detectable vitellogenin mRNA, more than 80% of the estrogen receptor is located in the nucleus (550 high affinity estrogen binding sites/nucleus), while the cytoplasm contains only 100 high affinity estrogen binding sites/cell. Administration of estradiol-17 beta, which induces massive synthesis and accumulation of vitellogenin mRNA, induces the estrogen receptor as well. The nuclear receptor level rises to approximately 2,000 estrogen binding sites/cell, while the cytosol receptor increases to only 150 sites/cel. Liver cells of male X. laevis which have been withdrawn from estrogen for 70 days exhibit a striking change in receptor levels. The nuclear receptor returns to the level prevailing in unstimulated cells (approximately 500 sites/cell) while the cytosol receptor level rises to more than 1,200 sites/cell (equivalent to 260 fmol/g of tissue). The existence of a pool of cytosol receptor, which is rapidly available for induction of vitellogenin mRNA, may in part explain the shorter lag period and more rapid induction of vitellogenin mRNA observed during secondary estrogen stimulation of withdrawn Xenopus liver cells.

Publisher Summary Recent research has aided in a substantial increase in the knowledge of basic bone metabolism. Bone is a dynamic tissue that continuously undergoes remodeling. Approximately 10% of cortical bone, the dense, mineral-rich bone that comprises the shafts of long bones, and 20%-40% of the trabecular bone, cancellous bone found in the interior of vertebrae and in the medullary space of long bones, is remodeled each year in the healthy adult. In this process, multinuclear osteoclasts resorb bone releasing mineral and matrix peptide constituents. This resorption is linked to a rebuilding process, in which osteoblasts replace eroded bone tissue. Osteoporosis (OP) is a debilitating progressive loss of bone mineral that ultimately manifests itself in elevated fracture rates, generally among those over age 45. OP is most prevalent among postmenopausal women, but affects both the sexes. Traditionally, modulation of the endocrine system has been the preferred approach to the management of OP. This chapter explains the topics in preclinical bone metabolism research as well as significant new developments in clinical management of OP. Practical in vitro and in vivo models are now available to serve as a basis for the study of synthetic mediators of bone mechanism. Thus, the development of novel therapeutic approaches to the clinical management of disease represents a significant opportunity in medicinal chemistry.

Despite remarkable advances in our understanding of the organization of eukaryotic genes, the mechanisms by which eukaryotic gene expression is regulated remain one of the major unresolved questions in biochemistry and molecular biology. A major approach to this problem has been through analysis of the mechanisms of steroid hormone action at the gene level. For the last several years we have been investigating the estrogen induction of vitellogenin gene transcription in liver cells of male Xenopus laevis and using this as a relatively simple model system for regulated gene expression in eukaryotes.

Administration of estradiol-17β to male Xenopus laevis evokes massive liver synthesis of the egg yolk precursor protein, vitellogenin, and its cognate mRNA. Since previous experiments had implicated only a nuclear estrogen receptor in vitellogenesis, we examined Xenopus liver cytosol for other estrogen-binding proteins. Cytoplasmic extracts from unstimulated Xenopus liver contain high levels (approximately 500,000 sites/cell) of an estrogen-specific binding protein. This protein exhibits a Kd of approximately 4 × 10−8M for estradiol-17β, binds estrogenic steroids only, and has a sedimentation coefficient in the range 2–3 S. It is not a classical estrogen receptor, as it does not translocate into the nucleus following estrogen administration. We discuss possible functions of this protein, which include a role in the ontogeny of the vitellogenic response, and in the cytoplasmic transport and storage of estrogen.