Disease relevance of Sftpb

• We constructed replication-deficient, recombinant adenovirus vectors in which a constitutive viral promoter drives the expression of the DNAs for the surfactant-associated proteins, SP-B (AdCMV.SP-B) and SP-A (AdCMV.SP-A) [1].
• Lung surfactant protein (SP)-A, SP-B, SP-C, and SP-D mRNA expressions were similar between control and IUGR rats [2].
• CONCLUSION: T3 attenuated sepsis-induced surfactant dysfunction and SP-A and SP-B transcriptional changes during sepsis [3].
• CONCLUSION: In this acute lung injury model, the effects of replacement therapy with surfactant consisting of synthetic phospholipids, SP-B and SP-C, were the same as those observed with MNS [4].
• These findings indicate that the decrease in SP-B and SP-C mRNA in fetuses of STZ-DB rats may be, in part, due to a direct effect of hyperglycemia, whereas the decrease in SP-A mRNA content in STZ-DB rats appears to be due to other effects of diabetes in pregnancy [5].

High impact information on Sftpb

• Furthermore, the data imply that the difference between plain PL surfactant preparations and bovine-derived surfactant preparations containing both SP-B and SP-C can be overcome by addition of SP-C [6].
• In addition, electron micrographs reveal the formation of tubular myelin structures from in vitro preparations using SP-B(9-36) in place of porcine SP-B indicating that the peptide has the potential to mimic this property of the native protein [7].
• In newborn rats exposed to hyperoxia on Days 3 through 10 of life, lung messenger RNAs (mRNAs) for SP-A and SP-B gradually and progressively increased, relative to levels in age-matched, air-exposed newborns, over this 8-d period [8].
• Corresponding increases in protein binding to the SP-B promoter were demonstrated by gel shift analysis [9].
• HNF-3 and TTF-1 transcription factors are known to stimulate SP-B transcription [9].

Biological context of Sftpb

• At fetal day 18, SP-B was barely detectable by immunohistochemistry in control animals but the levels were progressively increased through gestation and easily detected by fetal day 21 [10].
• At all fetal ages, SP-B was decreased in the STZ group compared with control animals [10].
• Dexamethasone inhibited type II cell proliferation but increased expression of SP-B [11].
• We conclude that respiratory distress after bleomycin in rats results from surfactant dysfunction in part secondary to selective downregulation of SP-B and SP-C [12].
• We have examined sequential analysis of histopathology and gene expressions of surfactant protein A (SP-A), SP-B, and SP-C mRNA in alveolar type II cells of rats with lipopolysaccharide-induced (LPS-induced) lung injury [13].

Anatomical context of Sftpb

• In contrast, in bronchiolar epithelial cells of diabetic lungs, the relative abundance of silver grains for SP-A mRNA increased approximately 2-fold above controls, while SP-B mRNA decreased slightly [14].
• The abundance of mRNAs for SP-B and SP-C also increased in day-17 fetuses after either 1 or 3 d of DEX treatment.(ABSTRACT TRUNCATED AT 250 WORDS)[15]
• Type II cells that were co-cultured with lung fibroblasts showed significant increases in messenger RNA (mRNA) levels of surfactant protein (SP)-A, SP-B, SP-C, and SP-D [16].
• Tissue in situ hybridization showed that dexamethasone stimulated the levels of SP-B mRNA in cells from both the alveolar and bronchiolar epithelium [17].
• NO production by alveolar macrophages, that the effect is due to a reduction in iNOS protein levels, and that the surfactant component responsible for the reduction is SP-B [18].

Associations of Sftpb with chemical compounds

• To address the question of whether secretion of SP-B and SP-C is stimulated by the same agonists that stimulate phospholipid secretion, we measured secretion of all four SPs under the same conditions used to measure phosphatidylcholine secretion [19].
• Secretion of SP-B and SP-C was stimulated three- to fivefold by terbutaline, 5'-(N-ethylcarboxyamido)adenosine, ATP, 12-O-tetradecanoylphorbol 13-acetate, and ionomycin [19].
• Except for SP-A, the cellular distribution of SP-B, -C, -D and CC10, studied with in situ hybridization and/or immunohistochemistry, did not change in room air nor in hyperoxia [20].
• Delayed hydrophobic surfactant protein (SP-B, SP-C) expression in fetuses of streptozotocin-treated rats [10].
• We found that retinoic acid interferes, in a dose-dependent fashion, with the expression of epithelial genes that are found in distal segments of the fetal lung (surfactant-associated proteins SP-A, SP-B, and SP-C) [21].

Physical interactions of Sftpb

• Footprinting analysis indicated that SP-A-induced protein binding to SP-B promoter was greater in amount, but not different in location, from that seen in control cells, which normally transcribe SP-B [9].

Regulatory relationships of Sftpb

• In this report, we have examined the hormonal regulation of the rat surfactant protein B (SP-B) mRNA to determine whether SP-B expression is coordinately regulated with the surfactant phospholipids or with SP-A [17].
• However, TGF-beta 3 did inhibit the increase of SP-B, SP-C mRNA levels caused by dexamethasone (100 nmol/L), in a dose-dependent manner [22].

Other interactions of Sftpb

• Regulation of SP-B and SP-C secretion in rat type II cells in primary culture [19].
• CONCLUSIONS: The effects of nitrofen in fetal rat lungs are reversed in part by antioxidant vitamins by upregulating the expression of TTF-1, HNF-3beta, and SP-B [23].
• This pattern of SP-D mRNA expression was compared with the expression of the other surfactant proteins and found to be most similar to that of SP-B [24].
• Examined by nuclear run-on assays, mechanical distention caused changes in transcriptional rates of RTI 40, SP-B, and SP-C [25].
• Furthermore, TGF-beta 3 had no direct inhibition on the increase of SP-B, SP-C mRNA induced by dexamethasone in type II cells, but had an indirect inhibitory effect mediated by fibroblasts [22].

Analytical, diagnostic and therapeutic context of Sftpb

• Western blots demonstrated expression of these proteins, including appropriate processing of the hydrophobic protein, SP-B [1].
• Both SP-B and SP-C mRNA were detectable at fetal day 18 in the control group and increased with advancing gestational age [10].
• The abundance of mRNAs for SP-A, SP-B, and SP-C per fixed amount of total cellular RNA was also determined in lungs from treated and control male and female fetal rats by Northern blot analysis [15].
• The expression of the messages for SP-A, SP-B, and SP-C was assessed by the reverse-transcriptase polymerase chain reaction (RT-PCR) [26].
• Further analysis by ELISA confirmed the reduced levels of SP-B in SM rats [27].

References